Spring 2018 Tester Symposium Abstract Listing

Agis, Aziz. Honolulu Community College
Native Hawaiian Restoration: Aihualama Stream Quality

Restoration sites for native species have been a priority for the Hawaiian Islands in an attempt to improve and restore the land to prior conditions. In the valley of Manoa, Aihualama Stream is congested with non-native plants that are listed for immediate removal by Lyon Arboretum because of the competitive impact these non-native plants can have on the surrounding plants. For this study, three sites along Aihualama Stream, including a control group, will compare the following parameters to one another, before and after, the removal of weedy plants and the planting of native plants. These parameters will be compared to samples collected during storm conditions to see the overall stream water quality as the plants progress and establish themselves in the environment. The data that is being collected includes turbidity, pH levels, dissolved oxygen, temperature, flow rate, nutrient absorbance, and salinity. This work examines the effect that native plants species have on the above listed stream water qualities compared to the effect that weedy plants have on stream water quality. Planting native plants along and inside the riverbed will improve stream water quality compared to the control group which is located upstream and surrounded by non-native plants.

 

Akiona, Anela, Marine Biology
Predatory fish population dynamics and diet in a traditional Hawaiian fishpond

Traditional Hawaiian fishponds, or loko iʻa, are a low-impact and culturally significant food source in the face of climate change and increased concerns over food security.  Heʻeia Fishpond, on the windward side of Oʻahu, is currently trying to raise herbivorous fish as a local and sustainable food source.  It is therefore crucial to understand the dominant predatory fish and their potential impact on the food production species.  A mark-recapture experiment (the Lincoln-Petersen closed population estimator with Chapman correction) was conducted to estimate the population of predatory fish in the pond, and visual, genetic barcoding, and stable isotope analyses were used to assess their diet.  Catch-per-unit-effort data from community fishing days were also utilized.  Sphyraena barracuda had the largest population at just under 200 individuals, follwed by Caranx ignobilis (89) and C. melampygus (19), which reflects trends in the CPUE from September 2016 - September 2017.  Diets of the three species consisted mainly of nearshore, estuarine fishes and crustaceans.  We did not find a large proportion of the native herbivorous fishes typically raised as food, suggesting that they are not specifically targeted by the dominant predators in the fisphond.  Maintenance of the current population of predators appears sufficient to allow the growth of the food production species as Heʻeia Fishpond continues to be restored.

 

Altman-Kurosaki, Noam, Marine Biology
Identifying feedback loops between primary production, herbivorous fishes, and fisher preference in coral reef subsistence fisheries

Many communities throughout the tropical pacific rely on fishing for subsistence. Through fishing, humans play a structuring role on coral reefs similar to that of an apex predator. However, these reefs are often overfished. Overfishing diminishes biodiversity and removes key herbivorous fishes, threatening ecosystem stability and increasing the risk of coral-algal phase shifts. While the impact of fishing on marine food webs is well-documented, the effect that diminished biodiversity has on ecosystem productivity is understudied, especially the strength of fisher prey preference in structuring coral reef fish communities.

I propose to address the question of how fisher preference alters the functional diversity of herbivorous fish and primary producers on Hawaii’s coral reefs, and how this in turn affects fishery productivity. I will first gain an approximation of prey preference through the distribution of pair-wise comparison surveys to communities throughout the MHI, in which participants will be asked to rank their preference of common reef fish species. I will then conduct field surveys of the neighboring reefs to determine how this fishing preference affects fish assemblages, fish size, and benthic community structure. I will also approximate algal productivity through the deployment of algal settlement tiles at each site. Collectively, this study will allow me to identify potential feedback loops between 1) how fish preference influences fish assemblages and fisheries productivity, 2) how fish assemblages influence algal growth and productivity, and 3) how algal communities affect fish assemblages.

 

Anderson, Taylor, GES
Developing a Low-Cost Sensor for Comparative Analysis of High Frequency Wind Speed Fluctuations

The goal of my project is to design, test, and build an instrument to accurately measure atmospheric wind speed fluctuations. I am using a Raspberry Pi Zero, an economical pitot pressure wind sensor, and a 3-D printed housing to keep the overall cost of the instrument as low as possible. This instrument will be calibrated and tested against two Kestrel 5500 Weather Meters with respect to accuracy against high and low wind speeds in both the lab and various locations around the west side of Oahu. The challenge of this project is tuning the pitot tube pressure sensor and the analog to digital converter (ADC) to attain the highest level of accuracy possible, in addition to designing a housing that will be small and lightweight but also orient the module directly into the wind. This is critical, as the pitot tube measures the pressure directly against the hole on the end of the tube.

However, a pitot pressure wind sensor will provide high frequency measurements that turbine and cup based anemometers have difficulty quantifying, due to the momentum of the propeller having a lag as the wind speed shifts and they spin up and down. My instrument will therefore provide more detailed wind speed measurements than many conventional meters, at a fraction of the cost. This will allow for the deployment of multiple units in the field to gain even more accurate data on the spacial and temporal fluctuations of the wind.

 

Arencibia, Daniel, Department of Biology
Alexa D. Foster, Department of Natural Resources and Environmental Management, University of Hawai‘i at Mānoa
Zinnia J. Dagostino, Department of Biology, University of Hawai‘i at Mānoa
Rebecca Katz, Department of Biology, University of Hawai‘i at Mānoa
Lane Morrow, Department of Biology, University of Hawai‘i at Mānoa
Kaylee Rowe, Hawai'inuiākea is Kamakakūokalani Center for Hawaiian Studies, University of Hawai‘i at Mānoa
Invasive macroalgae dominate Waikīkī Beach: A reassessment of community structure after 50 years

Long-term quantitative datasets in tropical areas are rare, yet needed for comparisons to present community states to identify temporal patterns and inform management of culturally and ecologically important species. From 1966 to 1969, M. Doty and colleagues (Doty et al. 1969) intensively surveyed the biomass and species composition of macroalgae, or limu, in 12 plots from 0 to 230 m offshore of the Waikiki Natatorium War Memorial, south O‘ahu. Our goal was to resurvey three of these plots (10, 110, and 210 m from shore) using the same methodology as Doty et al. 1969 to identify changes in the species composition and abundance of macroalgae over the past ~50 years. In 1967, the most abundant nearshore (10 m) species were Ulva spp., the invasive Acanthophora spicifera, Dictyosphaeria cavernosa, and Valonia aegagrophila while the offshore sites (110 and 210 m) were dominated by a high abundance of the native brown algae Sargassum spp. (limu kala), Dictyopteris plagiogramma (limu lipoa), and Padina sp.. The species composition in 2018 dramatically shifted to a high abundance of the invasive species Gracilaria salicornia and an absence of large brown algae such as Sargassum spp. and D. plagiogramma. The loss of these culturally important native species and increase in invasive species suggests this area has undergone a dramatic shift in community assemblage structure, with unknown ramifications for this area’s food web dynamics, fisheries habitat function, and ecology.

 

 

Balaan, Chantell, Developmental and Reproductive Biology
Motoko Iwashita, Department of Biology, UH Manoa
Dr. Ryan Lee, Milestones, Neurodevelopmental Center, Honolulu, HI
Masato Yoshizawa, Department of Biology, UH Manoa
Astyanax mexicanus autism spectrum disorder (ASD)- like phenotypic behaviors influenced by ketogenic diet

Autism spectrum disorder (ASD) is a pervasive, multifactorial neurodevelopmental disorder discernible in the earlier stages of child development. Recent studies suggested that the brain-gut reciprocal pathway, gut microbiota and metabolic process can play a vital role in the expression of ASD symptoms. In our latest study, the ketogenic diet, which induces a shift from glycolytic to ketogenic metabolic processes, mitigates symptoms in children with ASD (Lee et al., 2018). However, we are far from the full understanding of ASD systemic etiology. Here we utilize Astyanax mexicanus, a species of teleost composed of a surface and cave morphs, to determine the molecular pathways that connect gut and metabolic systems to ASD-like symptoms. The cave morph exhibits a battery of ASD-like symptoms: less social, adherence to a particular stimulus, hyperactivity, loss of sleep and repetitive behavior, and significantly reduced gut firmicutes. We then tested whether a ketogenic diet mitigates ASD-like symptoms in the cave morph. Both young and adult morphs (N~15 each) were treated with standard or ketogenic diets for ≥ 4 weeks and assayed for adherence behavior, hyperactivity and sleep duration. Our results showed that the ketogenic diet significantly reduced hyperactivity and increased sleep in the cave morph, however did not change adherence behavior. These are similar responses to those of ASD patients. We have recently developed assay systems for repetitive turning and social interaction. We will discuss how we plan to integrate these behavioral data with multiple -omics to acquire a full-view of systemic etiology in ASD-like symptoms.

 

Barba, Evan, Marine Biology (HIMB)
Molly Timmers, Hawai'i Institute of Marine Biology
Rob Toonen, Hawai'i Institute of Marine Biology, NOAA
Cryptofaunal community responses to reefscape changes: A case study of Jarvis Island’s 2015 bleaching event

How do coral reefs respond to changing global ocean conditions — more specifically, how do cryptic invertebrate communities rapid reefscape change? Warm seas exacerbated by El Niño in 2015 lead widespread coral bleaching (the phenomenon in which corals and their symbiont algae cease to coexist during high temperature periods). Jarvis Island at the equator was particularly impacted, resulting in substantial mortality, thus altering the reefscape in terms of live coral cover. But how does the cryptofaunal community respond? Jarvis is one of many Pacific wide sites monitored by the National Oceanic and Atmospheric Administration’s Ecosystem Sciences Division (NOAA-EDS) as part of their Pacific Reef Assessment and Monitoring Program (RAMP) cruises. As part of this monitoring, several sites are established to document. As part of this monitoring, several sites are established to document cryptic diversity using settlement units known as Autonomous Reef Monitoring Structures (ARMS). Essentially these structures provide complex artificial reef habitat to be inhabited over time. ARMS can then be recovered and processed to document both sessile and mobile inhabitants at a fine scale using morphological and genetic techniques. Prior to the beginning of the bleaching event in May of 2015, ARMS were recovered from a 2012 deployment, providing a snapshot of the community in a coral dominated state. Now in 2018 we will be returning to Jarvis in early to recover the ARMS deployed in 2015 that experienced a drastic reefscape change. We predict the post coral loss communities to have shifted in overall diversity, and by functional group.

 

 

Barba, Evan, Marine Biology (HIMB)
Emily Conklin, Hawai'i Institute of Marine Biology
Jon Whitney, Joint Institute for Marine and Atmospheric Research
Matt Iaccei, Hawai'i Pacific University
Rob Toonen, Hawai'i Institute of Marine Biology
Introducing AssessPool: a flexible pipeline for population genetic analyses of pooled sequencing data

Next-generation sequencing (NGS) is a powerful tool for examining genetic diversity, transforming genetic inference from single-marker studies to genome-wide investigations. If study questions only require population level resolution, pooling individual samples before sequencing (Pool-seq) can greatly reduce cost while producing allele frequencies of single nucleotide polymorphisms (SNPs). However, analyses of pooled data remains relatively difficult and unstandardized. Several programs have been developed specifically to handle Pool-seq data; however, most still require heavy formatting or substantial programming  skills to run. Here we introduce AsessPool, an open-source R and bash pipeline for Pool-seq analysis with a focus on population structure. AsessPool accepts a variant-call format (VCF) file and a FASTA-formatted reference, providing a straightforward transition from commonly used pipelines such as Stacks or dDocent. AssessPool can handle a variable number of pools and utilizes Popoolation2 to generate locus-by-locus pairwise FST values and associated Fisher T-test values as measures of population structure, and generates visuals to aid in assessing relationships between pools as well as coverage-based trends. With a VCF file of all SNPs identified as input, AssessPool i) filters SNPs based on adjustable criterion with suggestions for pooled data, ii) determines pool number and prepares proper data structure for analysis, iii) creates a customizable run script for Popoolation2 for all pairwise comparisons, iv) runs Popoolation2, v) imports Popoolation2 output, and vi) generates population genetic statistics and plots for data visualization. Here, a pooled ezRAD dataset generated from wild populations  is used to highlight features of the AssessPool pipeline for population genetic analysis.

 

Barkley, Yvonne, Marine Biology
Eva Nosal, University of Hawaii at Manoa
A Deep-Diving Dilemma: Improving the Accuracy of Location Estimates of Sperm Whales from Passive Acoustic Data

Sperm whales are deep-diving odontocetes present in ice-free waters throughout the world’s oceans. In the Hawaiian archipelago, these highly mobile, apex predators are primarily found offshore in water depths of at least 3000 m, which introduces challenges when assessing the population’s distribution and abundance in this region. Shipboard cetacean surveys use visual observer methods to estimate the number of whales and their perpendicular distances to the trackline for calculating population density and abundance using line-transect methodology. Passive acoustic methods are applied to complement visual observer efforts by detecting and tracking sperm whales using their echolocation click vocalizations emitted during foraging dives to depths up to 1900 m. Approximating perpendicular distances of sperm whales from acoustic data require a horizontal and depth component, which could lead to biased distances given inaccuracies in the latter component. This study aims to improve the accuracy of location estimates of sperm whales derived from towed linear array acoustic data by developing a localization technique that quantifies measurement error. Acoustic data from six cetacean surveys conducted in Hawaiian waters were analyzed for sperm whale clicks and surface reflections to calculate the estimated locations with measurements of uncertainty for 118 sperm whale encounters. Results of this study are useful for incorporating passive acoustic data into species distribution models that rely on accurate location information to determine an appropriate scale for the model for predicting sperm whale presence. Results may also provide a distribution of distances to fit a detection function for estimating sperm whale density and abundance.

 

Barkman, Alexandria, Marine Biology
Effects of the pesticide atrazine on the lace coral Pocillopora damicornis

Coral reefs worldwide are threatened by the effects of anthropogenic disturbances. Putative toxicants found in runoff may be one of the local stressors plaguing Hawaiian reefs. The goal of this study is to examine how the herbicide atrazine impacts the lace coral Pocillopora damicornis. Atrazine is an endocrine disruptor that has been shown to have negative impacts on reproduction in other marine organisms, but little has been done on the effects of atrazine on corals. P. damicornis is a simultaneous hermaphrodite that releases fully competent planula larvae.

P. damicornis colonies collected from Kaneohe Bay, Oahu were exposed to two concentrations of atrazine for one month. The low concentration of 2ug/L of atrazine has been found in water around Oahu, and the high concentration of atrazine, 10ug/L, is the EPA safe limit for aquatic systems.

The experiment ended prematurely due to mortalities. Polyp bailout was observed in corals exposed to 10ug/L of atrazine. This experiment will be repeated during the peak reproductive season to see if exposure to atrazine impacts the production and competency of larvae of exposed corals. Histology slides will also be made to look at the formation of gametes. Western Blot Gel Electrophoresis was used to detect expression of catalase, heat shock protein, cytochrome p450, superoxide dismutase, and cathepsin in experimental samples. Preliminary results indicate that atrazine has a negative impact on this species of coral. The development of coral specific biomarkers that indicate sublethal stress response to pesticide exposure could be valuable for diagnosing coral health.

 

Bond, Matthew, Botany
Dr. Orou Gaoue, University of Hawai‘i at Mānoa
Disentangling Biocultural Roots of Medicinal Plant Knowledge

Medicinal plants play a critical role in ecosystems, economies, and societies around the world. However, there is currently limited understanding of why people use some plants medicinally and not others. Traditionally, ethnobotanical research has been limited to testing how individual variables, such as age, correlate with medicinal plant knowledge. This research uses structural equation modeling to simultaneously test how medicinal plant knowledge is affected by the following variables: community-level plant availability, disease profile, illness risk, and historical legacies; and individual-level market economy participation and socio-demographic characteristics. Biocultural data were collected from four villages in Solomon Islands using interviews with every adult (315 participants), group interviews, plant diversity plots, and bioassays. Structural equation modeling was used to calculate path coefficients and test the causal links (both direct and indirect) between each variable and medicinal plant knowledge. Results show that community and individual-level variables have different effects on medicinal plant knowledge. This project (1) pinpoints generalizable principles of how people think about, categorize, and interact with their environment; (2) explores how societies make, maintain, and share knowledge; (3) advances the discipline of ethnobotany by assessing poorly-tested ethnobotanical theories and their interactions; (4) identifies characteristics of plants, ecological systems, humans, and cultural systems that are associated with different kinds and amounts of medicinal plant knowledge.

 

Brignac, Kayla, Oceanography
Polymer Identification of Plastic Marine Debris Throughout the Hawaiian Archipelago by FT-IR to Determine Sources

The Hawaiian archipelago is prone to marine debris accumulation due to oceanic and wind-driven currents. Marine debris has been quantified throughout the Hawaiian Islands, but never identified for its polymer composition. Different polymer types have varying degradation processes and absorbance rates of other pollutants, thus identification helps us understand their behavior in the environment. Therefore, this is the first study to analyze the polymer composition of plastic marine debris throughout the Hawaiian archipelago. Twelve beaches from Hawaii Island to Midway Atoll were sampled in triplicate, along with collections from sea surface debris at three locations near the Main Hawaiian Islands. Samples (n=4513) were analyzed using Attenuated Total Reflectance Fourier Transform Infrared spectroscopy to determine polymer composition. Polymer composition, and thus chemical density relative to seawater, significantly varied among beaches, indicating more ocean-based sources on windward beaches vs. more land-based sources on leeward beaches.  Supporting evidence includes higher concentrations of low density, floating polymers on windward beaches and high density, sinking polymers on leeward beaches; greater debris abundance on windward (n=9, 67.02 ± 101.54 g/m2) than leeward (n=3, 0.39 ± 0.29 g/m2) beaches with greater abundance correlating to less nearby land development (rs=-0.57, p=0.06); and higher concentrations of weathered plastics correlating to floating polymers on windward beaches than leeward beaches. Identifying the polymers comprising plastic marine debris can assist in the establishment of effective policy that regulates material acquisition, processing, distribution, use, recycling, and disposal. This is particularly important for the Hawaiian Islands due to its limited resources and geographic location.

 

Brush, Erik, Biology
Ryan N Jones, University of Hawaiʻi at Mānoa
Differences in fish recruitment to two congeneric coral species

Successful recruitment has prolonged effects on the population dynamics and community structure of coral reef fishes and influences behaviors of piscivores that consume new recruits. During the summer of 2017, we quantified recruitment of coral reef fishes to 20 coral colony clusters, each consisting of one antler coral (Pocillopora eydouxi) and the three nearest colonies of cauliflower coral (P. meandrina) at each of three different sites around Oʻahu. Every two weeks, we recorded new recruits, abundances of potential recruit predators (e.g. arc-eye hawkfish, Paracirrhites arcatus), and territorial competitors, such as blue-eye damselfish (Plectroglyphidodon johnstonianus). We also quantified the density of surrounding P. meandrina colonies within a 5-meter radius and coral colony size. A mixed effects general linear model indicated the number of fish recruits during the summer season was significantly greater on colonies of P. meandrina than on P. eydouxi, recruitment was greater on colonies of greater size, and recruitment to clusters was negatively correlated with surrounding densities of P. meandrina colonies. Additionally, higher abundance of P. johnstonianus was positively correlated with higher recruitment of other fishes on P. meandrina and not correlated with recruitment on P. eydouxi, indicating this territorial damselfish may affect recruitment of other fishes.  In contrast, the common Pocillopora associated predator, P. arcatus, showed no correlation with the recruitment of other fishes. These patterns suggest potential interactions between communities inhabiting these two congeneric coral species when colonies are located near each other and the potential importance of maintaining coral biodiversity on reefs to preserve these interactions.

 

Campillo, Luke, Biology
Robert C. Thomson, University of Hawaii
Anthony J. Barley, University of Hawaii
A comparison of reproductive isolation and coalescent species delimitation in Drosophila

Systematics is the field of evolutionary biology that aims to recognize and describe species in nature. A large and growing fraction of systematists define species as independently evolving lineages, which might be recognized by analyzing the population genetic history of alleles that are sampled from individuals belonging to those species. This has motivated the development of increasingly sophisticated statistical models, rooted in the multispecies coalescent process, that allow for simultaneous estimation of the number of species present in a sample of individuals, as well as the phylogenetic history of those species, using only DNA sequence data collected from many independent genetic loci. These methods hold extraordinary promise for increasing the pace and objectivity of species discovery, but require extensive validation to ensure that they are accurate and precise. Whether the species identified by these methods correspond to the species that would be recognized by alternative approaches (such as measurements of reproductive isolation) is currently an open question, and a subject of vigorous debate. Here we perform an empirical test of these methods by making use of a classic model system in the history of speciation research, flies of the genus Drosophila. Specifically, we make use of the uniquely comprehensive data on reproductive isolation that is available for this system, along with DNA sequence data, to ask whether Drosophila species inferred under the multispecies coalescent model are identical to those that have been recognized by many decades of speciation research.

 

Canfield, Sean, Biology
Brian Bowen, Hawaii Institute of Marine Biology
Population Genetic Structure and Connectivity in the California Horn Shark (Heterodontus francisci)

In the marine environment, population structure in organisms with high dispersal capability and pelagic larval stages has been well investigated. However, far less attention has been paid to population structure and genetic connectivity in fishes with limited dispersal capability and life-history characteristics that may result in local recruitment. Many benthic chondrichthyans (cartilaginous fishes, including sharks and rays) possess these traits, making them an ideal model for further understanding how these characteristics relate to population structure.

The California horn shark (Heterodontus francisci) is a small, benthic shark inhabiting the East-Pacific coastline from California to Mexico. This species is known to maintain small home-ranges as adults and exhibit extremely high levels of site-fidelity. Additionally, there is morphological evidence to indicate that the populations on the California mainland may be reproductively isolated from the Santa Catalina Island (CA) population – separated by only 30 kilometers of deep water.

To assess population connectivity in this species, samples were collected from near-shore locations along the California mainland and from Santa Catalina Island. DNA was extracted, and a 724-basepair portion of the mitochondrial control region (CR) was amplified and sequenced. Fst and φ-st were calculated to assess isolation between putative populations. Significant population structure was detected between Santa Catalina Island and the mainland (φ-st = 0.31). This represents the greatest level of differentiation detected over such a small distance (~30 km) in any species of shark to-date, suggesting that low dispersal capability can have profound effects on population genetic structure in the marine environment.

 

Carlson, Bailey, Biology
Claire Lewis, Biology
Biogeographic history of Echinometra mathaei in the Indo-Pacific

The history and frequency of colonization of the Hawaiian archipelago can be investigated in one of two ways: direct observations of species in the fossil record or indirect inferences using genetic data. Because the fossil record only captures some types of organisms, genetic methods have proven particularly useful because colonization events are expected to create predictable patterns of genetic variation. In Hawai'i, recently colonized species should exhibit uniformly low genetic diversity, as island colonization presumably involves dispersal of a relatively small number of individuals.  This project focuses on the sea urchin, Echinometra mathaei, which in earlier studies, was found to have no mtDNA variability within Hawai'i. However, the mtDNA genome is sensitive to genetic drift but is nonrecombining, so strong selection on a single nucleotide position has the potential to eliminate variation across the whole mtDNA genome. To distinguish among these hypotheses, I am analyzing genome-wide data sets, using next generation sequencing, from 110 samples of E. mathaei collected from Oahu, Hawai'i Island, Guam, Marshall Islands, Japan, American Samoa and Palau. The sequence data will be analyzed with a combination of classical, coalescent, and simulation-based methods that can distinguish among selection, a recent colonization, or a genetic bottleneck.

 

Caruso, Carlo, Marine Biology
Stanley Lio, University of Hawaii Manoa
Ruth Gates, University of Hawaii Manoa
Testing an underwater embedded RGB sensor for obtaining quick quantitative color data from corals.

Coral color is an important observable trait.  Color scoring can be used diagnostically in assessing coral health and has been widely utilized to monitor coral bleaching.  Multiple approaches to scoring color have been employed ranging from matching coral to color swatches by eye to color correction and sampling algorithms applied to photographs. These methods tend to be subjective, time consuming, or both.  To assess if a simple device could provide a quantitative instant reading of color that is feasible and useful, we built a prototype underwater color reader based on a simple commercially available 3-channel sensor chip.  We integrated the sensor chip with a microprocessor, memory card, OLED display screen, battery pack, and momentary switch in a nominally waterproof housing.  We programmed the microprocessor to write RGB (red, green, blue) values to a csv file whenever the button is pressed and display a data ID number on the screen.  When triggered, the device illuminates the subject with a fixed level of white light and captures readings from each channel on a scale from 0-255.  We tested the color reader on samples of Monitpora capitata coral and a set of color standards.  Repeated measurements of numerous individual coral samples were taken and single readings on individual corals were recorded at various time points during a heat-stress experiment.  Color standards were tested to assess instrument consistency and drift. In this poster, we share the trial performance results and future plans for this instrument.

 

Caruso, Carlo, Marine Biology
Jen Davidson, University of Hawaii – Manoa
Ruth Gates, University of Hawaii - Manoa

Examining the distribution of heat-induced stress susceptibility in a coral (Montipora capitata) population.

 

Some corals resist heat-stress induced bleaching more than others, indicating population plasticity that might enable reefs to persist under hotter climate scenarios.  During the 2014 and 2015 bleaching events in Kaneohe Bay, researchers observed many instances of side-by-side corals of the same species exhibiting starkly different levels of bleaching.  Some resilient coral stocks were identified based on performance during the bleaching event and under experimental heat stress.  We are curious how these coral stocks fit into the population level distribution of responses as this has ramifications for selecting resilient stock for Assisted Evolution strategies.  Do they represent the upper limit of thermal tolerance available in the population or are there even hardier genotypes out there?  Propagules from 150 individual M. capitata colonies across Kaneohe Bay, 8 previously identified resilient genotypes, and paired colonies with known bleaching phenotypes were exposed to a prolonged artificial heat stress. Temperature was gradually ramped from a baseline of 25 C until >50% mortality was evident (~32.5 C) at which time temperature was released to 29 C.  Photosystem health was assessed by PAM fluorometry and corals were photographed to assign health scores and color values.  These metrics will be used to examine the overall distribution of thermal stress tolerance, how the selective stocks compare with the general population and each other, and the relative spread of intra-genotype variation.  In this poster, we share the preliminary analysis and future work suggested by our results.

 

Chen, Jessica, Department of Microbiology
Iwanicki, Thomas, Department of Biology, University of Hawaii at Manoa
Goetze, Erica, Department of Oceanography, University of Hawaii at Manoa
Blanco-Bercial, Leocadio, Bermuda Institute of Ocean Sciences
Maas, Amy E. , Bermuda Institute of Ocean Sciences
Porter, Megan L., Department of Biology, University of Hawaii at Manoa
Identification and Analysis of novel Luciferase and Opsin Genes in the Bioluminescent Copepod genus, Pleuromamma

Bioluminescence, the biochemical production of light by living organisms, is produced by both terrestrial and marine species. Bioluminescence can be used for courtship, predator-prey defense mechanisms, and intra-specific communication. Because bioluminescence is the result of convergent evolution, there is a diverse range of bioluminescent compounds and reactions. The marine zooplankton genus, Pleuromamma, consists of over sixteen bioluminescent species, with many species having multiple luciferase genes. Currently, there are no published data on opsins and incomplete data on luciferases within the Pleuromamma genus. Transcriptomic analysis of Pleuromamma species can reveal the phylogenetic relationships between opsin and luciferase genes both intraspecific and interspecific.

RNA was extracted from three individuals each  of seven Pleuromamma species - P. xiphias, P. abdominalis, P. antarctica, P. robusta, P. quadrangulata, P. gracilis, and P. piseki. Confirmation of morphological identification was done using COI sequences. We will use known copepod luciferase and opsin genes, specifically Metridia luciferase and known Calanoida opsins, to annotate the assembled Pleuromamma transcriptomes. Replicates will permit us to quantify luciferase and opsin expression.

Transcriptome sequencing and analysis will contribute to known luciferase findings within P. xiphias and P. abdominalis and identify novel luciferases and opsins within the Pleuromamma genus. The completed data set will allow for the phylogenetic analysis of luciferase and opsins, determination of the relationships between luciferase and opsins and examination on the origins of bioluminescence in the Pleuromamma genus.

 

Chi, Megan, Molecular Biosciences and Bioengineering
Dr. Jon-Paul Bingham (Bingham, JP), Department of Molecular Biosciences and Bioengineering
Structurally enhancing Conus virgo peptides with hydroxyprolines: The hidden gem to parasitic drugs that target rat lungworm.

Conotoxins have received a great deal of attention as promising novel leads in drug development. These types of peptides can target a wide range of neurological ion channels and membrane-bound receptors. This study explores the stabilization of a novel α-conotoxin in Conus virgo by using hydroxyprolines and peptide backbone cyclization as tools for pharmacological enhancement. The focus on this specific α-conotoxin is due to its unique three potential sites for proline hydroxylation. Hydroxyprolines and cyclization have been observed to augment the stabilization of peptides, to reduce enzymatic degradation, and to promote increased oral bioavailability – a highly prized pharmaceutical characteristic.

In this specific research, α-conotoxins possess the capacity to selectively paralyze worms by the inhibition of the α3β2 acetylcholine receptor subtype. By this selective nature, α-conotoxins may have a potential as anthelmintic drug leads. Thus, bioengineering α-conotoxins may naturally lead to targeting parasitic diseases such as rat lungworm (Angiostrongylus cantenosis) found in Hawaii. Thus, our objective is to seek an alternative to intra-spinal and to less efficacious broad-spectrum compounds that are currently used as anthelmintic drugs. Here, we will use the techniques of reversed-phase high-performance liquid chromatography, mass spectrometry, oxidation reactions, and bioactivity by LD50 with receptor assays in worms, to assess production and bioactivity of our lead peptide candidates. We expect to be able to influence the stability of this α-conotoxin with hydroxyprolines and cyclization while continuing to elucidate the pharmacological limitations in peptide drug design. This work is in-part is funded by the USDA HATCH 5028H (Bingham).

 

Chung, Anne, Marine Biology
Lisa Wedding, Stanford University, Center for Ocean Solutions
Grace Goldberg, University of California, Santa Barbara, SeaSketch
Alison Green, The Nature Conservancy; Amber Meadows, Hawaii Coral Reef Initiative
Alan Friedlander, University of Hawaii, National Geographic Society
Mark Hixon, University of Hawaii
Design Principles to Build Coral Reef Resilience through Spatial Herbivore Management in Hawai‘i

Coral reef managers currently face the challenge of mitigating local stressors to promote ecological resilience in response to a warming and acidifying ocean. The effective management of herbivores is one local action that managers can take in order to control overgrowth of benthic algae and accelerate recovery following coral bleaching events.  One approach has been to establish Herbivore Management Areas (HMAs) where the take of herbivorous fish is prohibited. However, there are currently few design principles to guide the implementation of a network of HMAs as a resilience-building tool.  We applied a systematic conservation planning approach to develop a set of design principles for herbivore reserve networks adapted specifically to enhance coral reef resilience in Hawai‘i.  These results can be used to guide future design of HMA networks globally as well as support the implementation of a resilience-based spatial management approach across the main Hawaiian Islands.

 

Coffey, Daniel, Marine Biology Graduate Program, Hawaii Institute of Marine Biology
Mark Royer, Hawaiʻi Institute of Marine Biology, University of Hawai'i at Mānoa
Carl Meyer, Hawaiʻi Institute of Marine Biology, University of Hawai'i at Mānoa
Kim Holland, Hawaiʻi Institute of Marine Biology, University of Hawai'i at Mānoa
Contrasting diel patterns in swimming behavior of a vertically migrating deepwater shark

Advances in biologging technologies have significantly improved our understanding of the spatial ecology of marine animals in relation to their dynamic environment. With the recent advent of oxygen-sensing tags, the relative importance of temperature and dissolved oxygen on the vertical distribution and behavior of fishes may be better assessed. We used a combination of a novel temperature-depth-recorder capable of measuring and logging dissolved oxygen data and a tri-axial accelerometer to investigate the fine-scale swimming behavior (tail beat frequency, overall dynamic body acceleration [ODBA]) of a vertically migrating deepwater shark, the bluntnose sixgill (Hexanchus griseus). This is the first study to combine this suite of biologging technologies and revealed distinct changes in behavior across mesopelagic environments occupied during diel vertical migrations. Overall dynamic body movements were greater during shallower (200-350 m), nighttime distributions at warmer temperatures (10-13 C) and higher dissolved oxygen saturations (70-80%) compared to deeper (500-700 m), daytime distributions in cold (5-6 C), low oxygenated (15-25%) waters. However, ODBA declined when water temperatures exceeded 13 C. Acquiring contemporaneous in situ measurements of dissolved oxygen alongside temperature, depth, and accelerometry data greatly enhances our ability to identify how oceanographic conditions drive patterns in the distribution and behavior of marine animals.

 

Coffey, Bethany, Marine Biology
Tim Tricas, Zoology, University of Hawaii at Manoa
Triggered: Context matters for vocal reef fish

Communication between individuals can reduce social disorder, allow for more efficient cohabitation, and enhance individual fitness.  Acoustic signals are a common form of communication in both terrestrial and aquatic environments.  Several families of reef fish are known to produce acoustic signals in the contexts of territorial defense, courtship, and distress.  The highly derived triggerfishes have evolved several sound production mechanisms, but the function of different sounds in communication behavior within species is unknown.  This study tested the hypothesis that the humuhumunukunukuāpua'a, Rhinecanthus rectangulus, produces context-specific sounds when interacting with conspecifics or predators.  The humuhumu produced five different sound types in the presence of a conspecific and in the presence of a moray eel predator:  The Snap, Drum, and Drum-Snap sounds are vocalizations, whereas Substrate Bite and Grind are incidental sounds produced during feeding.  The Snap sound was produced most frequently during interactions with a conspecific, and Drums most frequently during interactions with the moray eel predator.  High speed video confirms that Drum sounds are produced by stridulation of the pectoral fins, and Snaps are produced in association with rapid movement of the oral jaws.  This is the first study to experimentally demonstrate biologically relevant context-dependent vocalizations in a marine fish.  Context-specific vocalization likely increases humuhumu fitness by reducing miscommunication and wasted energetic resources, as signals are beneficial and costly produce.  Future studies will focus on the function of the different vocalizations, as it is unknown if they are the result of selective pressures for effective communication with conspecifics or predators.

 

Coleman, Richard, Zoology
Joshua M. Copus, Hawaii Institute of Marine Biology, Dept. of Biology
Daniel M. Coffey, Hawaii Institute of Marine Biology
Robert K. Whitton, Bernice Pauahi Bishop Museum
Brian W. Bowen, Hawaii Institute of Marine Biology
Shifting reef fish assemblages along a depth gradient in Pohnpei, Micronesia

Mesophotic coral ecosystems (MCEs) continue to be understudied, especially in island locations spread across the Indo-Pacific Ocean. Pohnpei is the largest island in the Federated States of Micronesia, with a well-developed barrier reef, and steep slopes that descend to more than 1000 m. Here we conducted transect surveys along a depth gradient of 0 to 60 m in addition to video surveys that extend to 130 m to test for changes in reef fish composition from shallow to mesophotic depths. We observed 304 fish species across 47 families with the majority confined to shallow habitat. Taxonomic and trophic positions at 30 m showed similar compositions when compared against all other depths. However, assemblages were shown to be comprised of a distinct shallow (<30 m) and deep (>30m) group, suggesting 30 m as a transition zone between these communities. Shallow specialists had a high probability of being herbivores and deep specialists had a higher probability of being planktivores. Surgeonfishes, soldierfishes and wrasses were associated primarily with shallow habitat, while damselfishes, groupers, and anthiadines were associated with deep habitat. This study supports the 30-m depth profile as a transition zone between shallow and mesophotic ecosystems (consistent with accepted definitions of MCEs), with evidence of multiple transition zones below 30 m. Disturbances restricted to either region are not likely to immediately impact the other and both ecosystems should be considered in management of reefs near human population centers.

 

Copus, Joshua, Biology
Matthew Craig, NOAA-SWFSC
Joseph DiBattista, Australian Museum
Brian Bowen, Hawaii Institute of Marine Biology
Phylogeography of the squirrelfish Neoniphon sammara reveals Pliocene isolation across the Indo-Pacific barrier

Squirrelfishes (Neoniphon: Holocentridae) are nocturnal inhabitants of coral reefs, easily identifiable by their red coloration and relatively large eyes. Phylogeographic analysis of the Blood-spot Squirrelfish (Neoniphon sammara) was conducted to elucidate the evolutionary history of this widespread Indo-Pacific fish. We sequenced mtDNA Cytb for 314 specimens from 18 locations across the Red Sea, Indian Ocean and Pacific Ocean. The mtDNA results reveal highly divergent groups (sequence divergence d = 0.06) separated predominantly by the sporadic barrier between the Indian and Pacific oceans. However, mixed populations occurred at the East Indian Ocean location of Cocos and West Pacific locations of Palau and Palmyra, and only Indian Ocean haplotypes were recovered from Fiji. These results indicate Pliocene isolation (approximately 3 million years ago) across the Indo-Pacific Barrier followed by cryptic speciation and subsequent spread of the Indian Ocean form across the West Pacific. These findings support the hypothesis that isolation at the Indo-Pacific barrier is a primary source of reef fish biodiversity.

 

Costantini, Maria, Zoology
Lisa Crampton, Kauai Forest Bird Recovery Project
Floyd Reed, University of Hawaii at Manoa
The Effect of Captivity on the Gut Microbiota of a Critically Endangered Hawaiian Honeycreeper

The insectivorous honeycreeper, ʻakikiki (Oreomystis bairdi), a critically endangered forest bird on the island of Kauaʻi, is subjected to a suite of introduced threats and currently only occupies a small (54km2) region of its previous range. Captive breeding attempts have been recently initiated, and agencies are contemplating the potential establishment of translocated insurance populations. This project explores an overlooked, but potentially critical factor to the success of translocation attempts by analyzing the effect of captivity and novel environments on host microbiota. Symbiotic microbiomes provide key health benefits to the host through such processes as dietary supplementation, boosts to host immune system, increased pathogen resistance, or tolerance to environmental perturbations. Because gut microbiota are heavily influenced by diet and environmental conditions, differences in the microbiota of captive-raised individuals may hinder their ability to adjust upon reintroduction. Fecal samples were collected from wild ‘akikiki beginning during the spring of 2017, by mist-netting and collecting directly from the bird while in hand. Additionally, samples were collected directly from the birds in captivity. Samples will be analyzed using Illumina next-generation sequencing techniques of the 16S rRNA gene to determine bacterial community composition and diversity. The results from this analysis will better inform management strategies of this endangered bird, such as by developing an inoculation protocol for captive individuals, as well as will likely be informative for understanding similar species within and outside of Hawai’i.

 

Damiani, Laura, Marine Biology
The effects of the herbicide atrazine on the coral Montipora capitata

Atrazine, one of the most applied herbicides used worldwide, disrupts normal reproductive development in some animals.  Atrazine is used for agriculture in Hawaii and potentially threatens marine organisms after it enters the ocean through run-off.  Various pollutants and pesticides affect the health of corals, but atrazine’s effect on corals is unknown.  This study investigates the effects of atrazine on the early life history stages of the rice coral Montipora capitata, and the molecular response of M. capitata exposed to atrazine.  Fertilization assays were performed with M. capitata gametes exposed to select concentrations of atrazine.  In addition, adult M. capitata fragments were exposed to 2 and 10 μgl-1 atrazine for 5 days.  Along with monitoring for physiological effects, Western blot analysis was performed using the expression of xenobiotic metabolizing enzymes to detect stress at the cellular level.  Percent fertilization for the control was 70% after 5 hours, and percent fertilization for the treatments ranged from 38% (100 μgl-1 atrazine) to 77% (10 μgl-1 atrazine). Overall, there was no significant difference in percent fertilization between treatments.  This preliminary data indicates that atrazine does not greatly impact fertilization rates in M. capitata, but this experiment will be repeated using more replicates to increase the sample size.  Among the antibodies tested, cytochrome P450 1A1, HSP60, and superoxide dismutase showed expression in M. capitata exposed to atrazine as well as the controls, indicating a sub-lethal stress response.  In the future, other antibodies related to cellular stress response and reproduction will be tested. 

 

de Souza Brasil Barreto, Helena, Biology
Kathleen S. Cole , University of Hawaii at Manoa
Gonad Structure of Juveniles of the Hermaphroditic Goby Species, Eviota epiphanes (Teleostei: Gobiidae)

This study investigated the process of gonadal development in a serial hermaphroditic species of marine fish. We used Eviota epiphanes as a vertebrate model to examine the morphological structure of the ovotestis (e.g., a gonad that possesses both ovarian and testicular tissues) throughout the juvenile stage, to provide insight into ovotestis development. More specifically, this study focused on investigating the distribution of both ovarian and testicular tissues in the developing ovotestis of immature individuals. through histological assessment. We hypothesized that the relative proportions of ovarian and testicular tissues present in the ovotestis of Eviota epiphanes during the juvenile period may vary throughout development in response to social cues. Juvenile specimens were obtained to look at gonad morphology, and social experiments were maintained to access the possible role of social selection on sexual function prior to sexual maturity. The results of this study showed that when individual pairs of E. epiphanes juveniles are maintained together, the relative amounts of sex tissues are re-appropriated accordingly. This finding suggests social control of sexual differentiation and sexual function in this species. Furthermore, our results also demonstrated that the gonads of most, if not all, E. epiphanes juveniles first develop as an ovotestis. This information provides us with a better understanding of the factors involved with sexual differentiation and development of sexual function in a bi-directional hermaphroditic vertebrate.

 

Diaz, Ulises, G.E.S. - S.O.E.S.T.
Tracking Shoreline Morphology Using Drone Based Photogrammetry

Beaches around the world have huge economic, social, and recreational value to cities, which are based primarily on the aesthetic quality of the beach. Beaches have multiple factors that contribute to coastal erosion such as wind, sediment, wave, and tidal forces. In addition, each coastal area has its own unique geomorphological, geological, and biological systems that makes coastal topography surveys challenging. Beach profiling estimates sediment volume changes in any given coastal area and shows the health of the beach. These data overlays what sort of management schemes need to take place such as, beach recharge, barrage construction, beach nourishment, and manage retreat methods, to reduce coastal erosion. Generally, traditional ground-based surveys such as, 2-Dimensional horizontal shoreline and vertical beach profiles, tend to have limitation in expenses and time consuming in a large scale. Therefore, the Unmanned Aerial Vehicle (UAV) photogrammetry (the science in using photography in surveying and mapping to measure distances between objects) is a more simple and cheaper way in approaching large-scale data collection. Especially, in capturing the rapid coastal changes caused by natural processes. This project intends to accurately quantify the impact of high swell activity on beach faces over the course of a season using UAV drones with cameras and photogrammetry with the software agisoft. The project will focus on one beach, Rock Piles Beach over the 2017 – 18 academic year.

 

Dilley, Eric, Marine Biology
Demography of juvenile corals in contrasting environments

Recruitment, survivorship, and growth determine the abundance and distribution of coral colonies.  On Hawaiian coral reefs, Pocillopora is a common coral genus characterized by high recruitment and rapid growth.  To determine how demographic rates of juvenile Pocillopora vary with reef environment, the Hixon Lab constructed six cement modules (1 m^3 each) at both Hanauma Bay (protected healthy reef) and off Waikiki (unprotected degraded reef).  Colonized by coral larvae, these modules allowed us to track the fate of all individual colonies through time.  We tested the hypothesis that juvenile Pocillopora recruitment, survivorship, and growth will be greater at Hanauma Bay than Waikiki because benthic algal cover at Hanauma Bay is lower due to higher urchin abundance.  We found that coral recruitment (starting at a colony size of 1 cm2) was actually greater at Waikiki, although coral survival and growth rates were indeed greater at Hanauma Bay.  Because algal cover is much less at Hanauma Bay, where many urchins are present, reduced competition with algae likely contributes to higher observed Pocillopora survival and growth.   We conclude that juvenile Pocillopora corals in areas protected from fishing of herbivores will survive better and grow faster than corals on reefs dominated by benthic algae.

 

Dowell, Charis, Department of Psychology
Dr. Patricia A. Couvillon, Department of Psychology, Pacific Biosciences Research Center, University of Hawaii at Manoa
Foraging Honeybees Learn Preferences for Large and Small "Flower" Sizes

There is a widely-held view that bee foragers are predisposed to prefer larger over smaller flowers. However, recent research on the size preference of honeybees (Apis mellifera) and several species of bumblebees has not supported this view. Size preference  may develop by association of flower size with nectar rewards, and both large and small preferences may be produced by experience. Interest in the capabilities of honeybees to learn about relations among stimuli has led to the present experiment. Two groups of bees were trained with pairs of artificial flower stimuli of the same color that differed only in relative size (one larger and one  smaller).  Two additional groups of bees were trained with pairs of stimuli that differed in relative size but were not the same color. For Groups Large-Same and Large-Different, choice of the larger stimulus in the pair was rewarded with sucrose, and for Groups Small-Same and Small-Different, choice of the smaller stimulus was rewarded. There were 12 bees in each group and training was conducted with one bee at a time. On each of the 12 training trials, there was a novel pair of stimuli, always with one larger and one smaller. The results for the bees in the four groups were nearly identical. All groups quickly learned to choose the relative size that was associated with the sucrose, even though the actual stimuli were different on each trial. The results suggest that honeybees learn a relational concept of size.

 

Driscoll, Norma-Jean, Oceanography
Bacteriophage and Host Bacteria Interactions Within the Ala Wai Canal

An ecosystem consists of interacting organisms that include predator-prey relationships. The ocean, rivers, and streams all contain their own ecosystems and biota with predator-prey relationships. Marine bacteriophages, or also known as phages, are marine viruses that can be found in water sources that infect and kill specific types of bacteria. Much like a predator’s role in predator-prey relationships, bacteriophages are a source of death to their host bacteria. Currently within the Ala Wai canal, it is unknown how phages affect bacteria populations. Do some phages infect more than one type of bacteria? Are there bacteria populations that are resistant to certain phages? The Ala Wai canal is a location for recreational activities that may contain hazardous bacteria to humans. Properly identifying bacteria and the phages that infect them can potentially lead to phage therapy, which involves curing a bacterial infection through the use of bacteriophages. Interactions between the phage and the host bacteria also lead to DNA exchanges, which can play a role in bacteria evolution within their environment. Studying these interactions could provide data on bacterial evolution. I will be looking at how phages impact host bacteria populations as well as analyze which bacteria are more likely to survive in their environment via phage-host cross-reaction test. This test will take isolated phages for specific bacteria and test if they infect different isolated bacteria to get information on potential interactions within the Ala Wai.

 

Epps, Ashleigh, Marine Biology
Ariana S Huffmyer, Hawaii Institute of Marine Biology
Up, Down, or All Around: Directionality, linear extension, and growth patterns of two coral species in Kaneohe Bay

Plasticity, the capacity to alter structure, growth, or other aspects of an organism’s physiology, may allow organisms to succeed in response to changing environments. Specifically, reef-building corals may exhibit plasticity in growth structure and pattern, which may influence their performance and success in changing oceans as a result of global climate change. To investigate how coral growth (pattern and complexity) shift when exposed to a change in the environment, a transplant experiment took place in the Gates Lab at the Hawaii Institute of Marine Biology in Kaneohe Bay, in which the growth of corals was monitored over a six-month period. During this transplant experiment, corals were reciprocally moved between two reef sites (inner and outer bay reefs) that differ in physical conditions. Paired genotype samples of two species of corals (n=40 Montipora capitata, n=40 Porites compressa) were stained with a skeletal marker (Alizarin Red S). Directionality of growth, complexity, and linear extension were calculated and compared between genotype and environments. We examined whether growth patterns are more strongly influenced by genotype or environment and whether individuals shift growth patterns in response to the transplant. Measuring directionality of individual coral growth provides a unique perspective on reef ecosystem complexity, which is important for habitat availability for other organisms. It is important to understand the growth patterns of corals in response to a change in the environment and how coral reefs rebuild following disturbances such as bleaching events, disease outbreaks, and marine degradation.

 

Fang, Jenny, Molecular and Cell Biology
Menashe Elazar, Ph.D., Stanford University
Investigating the RNA epigenetic modification, m6A, in positive-stranded RNA viruses

Methylation of RNA is the most prevalent post-transcriptional modification in eukaryotic cells and nuclear-replicating viruses. 80% of all methylation occurs on adenosine in the N6 position (m6A), within the context of the conserved sequence GGACU. m6A methylation plays a crucial role in gene expression with its involvement in transcription regulation, RNA stabilization, and alternative splicing. Like mRNA, positive-sense single-stranded viral RNAs (+ssRNAs) are directly translated in the host cytoplasm. Across all 6 genotypes of Hepatitis C Virus (HCV), conserved m6A motifs were identified. We therefore hypothesize that +ssRNA genomes of viruses like HCV undergo m6A methylation during their life cycles. To test this, we sought to identify m6A in HCV and examine how the modification plays a role in the HCV life cycle. First, IVT unmethylated HCV RNAs were transfected into Huh7 cells and, following initiation of replication, extracted and immunoprecipitated with anti-m6A antibody. Candidate methylated viral RNAs were then detected by Northern blot and qRT-PCR. To assess the possible role of m6A in the HCV life cycle, assays of HCV genome replication and viral protein translation were performed in the presence of methylation inhibitors. Understanding m6A methylation in the context of +ssRNA viruses will provide new insights into their biology, hopefully, aid the development of novel antiviral therapeutics for important members of this family including Dengue and Zika viruses.

 

Fujimoto, Brent, Anatomy, Biochemistry, and Physiology
Amanda Lee, JABSOM
Ben Fogelgren, JABSOM
Noemi Polgar, JABSOM
The Exocyst Complex in Insulin Stimulated Glucose Uptake in Skeletal Muscle Cells

Objectives : The Centers for Disease Control and Prevention lists Diabetes as the 7th leading cause of death in America.  People who have type 2 diabetes mellitus are at a greater risk for numerous sequela, such as cardiovascular disease, renal failure, and limb amputation. Many of the related illnesses that are linked to type 2 diabetes are a result of the excess glucose in the blood.  Skeletal muscle cells are responsible for 80-90% of the insulin-induced glucose uptake.  When stimulated by insulin, skeletal muscle increases the amount of glucose transporter type 4 (GLUT4) on the cell surface. An eight-protein complex called the exocyst has been recognized to have a role in the insulin-induced exocytosis of GLUT4 vesicles in cultured adipocytes. However, it remains to be seen if the exocyst has a similar function skeletal muscle. We hypothesize that the exocyst complex in skeletal muscle is essential for insulin-stimulated glucose uptake and also glucose homeostasis on the organismal level.

Methods: To analyze exocyst-mediated intracellular trafficking in skeletal muscle in vitro, we utilized CRISPR/Cas9 to create Sec10 knockout clones from L6 GLUT4-myc myoblasts. Sec-10 is a central part of the exocyst where shRNA knockdown results in the down regulation of other exocyst components as well as a mitigation of the function of the exocyst complex as a whole (Zuo et al., 2009) L6 Sec10 knockout myoblast fail to uptake more glucose analog 2DG in response to 100nM insulin stimulation compared to untreated controls.  Moreover, Sec10 knockout clones uptake ~50% less than wild type cells given the same treatment.  Cellular fractionation reveals that Sec10 knockout cells are unable to traffic GLUT4 to the plasma membrane in response to insulin.  For in vivo studies, we generated a tamoxifen-activated skeletal muscle-specific Sec10 knockout mouse.  Four weeks after tamoxifen treatment, Sec10 skeletal knockout mice demonstrate impaired glucose tolerance.  However, there are no significant differences in serum insulin, HbA1c, and epididymal adipocyte size when compared to controls.

Conclusion: Based on our findings, the absence of Sec10 in mouse skeletal muscle cells disrupted glucose homeostasis due to defective GLUT4 trafficking. Ongoing work with skeletal muscle-specific Sec10 knockout with our new mouse model will provide valuable insights regarding the intracellular mechanisms that occur in skeletal muscle cells in response to insulin.  Moreover, our research will help to assess the likelihood of the exocyst complex as a potential therapeutic target for type 2 diabetes.

 

Goldberg, Scott, Northwestern University Department of Civil and Environmental Engineering and University of Hawaii at Manoa
Luisa A. Marcelino, Northwestern University Department of Civil and Environmental Engineering
Timothy D. Swain, Northwestern University Department of Civil and Environmental Engineering
Novel metrics for comparing coral bleaching responses in the context of their assemblages

As reefs around the world decline due to bleaching events, research is needed to better understand coral susceptibility. Any study is complicated because differential bleaching among corals is based on intrinsic factors of the coral holobiont and environmental factors affecting assemblages. Recent work has standardized comparing responses across 317 coral taxa j, based on surveys at 316 sites k and compiled into a matrix of bleaching responses Bjk . Averaging the responses of members of a taxon over all sites k where said taxon was found, retruns a taxon-Bleaching Response Index value. Conversely, when the matrix is averaged over all taxa j found at a site, siteBjk is obtained. There is also use for a taxon specific metric that relates the bleaching response of a species to its assemblage, thus compensating for environmental factors and reflecting the intrinsic characteristics of a taxon which affects bleaching response. Taxon-alpha and taxon-beta were created by comparing how an individual taxon bleached in comparison to its assemblage. Taxon-alpha (the intercept when graphing the average of responses of all corals minus taxon j at each site k against the responses of taxon j) describes how said taxon responds to weak stresses compared to its assemblage, while taxon-beta (the slope of the same graph) describes how a taxon responds to bleaching compared to its assemblage. Many corals either over-respond to weak stress with little response to more extreme stressors or bleach little under weak stress and bleach far more than the assemblage under great stress.

 

Greene, Austin, Zoology
Heat Fluxes and the Sea-Atmosphere Interface

Hawaii has seen steady decline in coral cover since 1968, due in part to declining water quality and increased runoff from intensifying coastal development. Sediments in the water column can disrupt physical and biological processes on coral reefs and increase coral disease. At present, sediment stress measures are typically collected in-situ, but remotely-sensed alternatives are needed to capture high spatio-temporal variability of sedimentation. Ocean color products from the VIIRS satellite may be a practical solution, allowing daily estimation of total suspended sediments in the water column (Kd (490)). VIIRS Kd (490) has not been validated in near-shore habitats by either NOAA or NASA, and current NOAA ocean color products are based on a coarse global algorithm. It remains to be seen how these satellite estimates of sedimentation reflect in-situ sedimentation that drives coral health. My research will use in-situ spectral measures to validate VIIRS Kd (490) products on three Hawaiian islands and assess how changing conditions influence the performance of satellite ocean color when estimating near-shore sedimentation. I will then combine validated VIIRS Kd (490) products with coral health surveys, watershed models, and in-situ sediment stress metrics to determine how ocean color correlates with coral health at watershed and island scales.

 

Hebert, Garrett, Global Environmental Science
Rain Gauge Analysis of Precipitation on Oahu

Contemporary methods for taking measurements at the atmosphere-sea interface for use in calculating heat flux are examined. Net heat flux is equal to the sum of solar radiation, emission of longwave radiation from the earth, latent heat, and sensible heat. Obtaining this data is important for modeling surface heat fluxes and for gaining more insight into meteorological and climate phenomena. However, due to the dynamic movement of the sea, wind flow modification in wave troughs, flow distortion around instrumentation, varying weather conditions, and other factors make taking direct measurements extremely difficult. Obtaining this data remains one of the most challenging problems in modern oceanography (Weller, 2008). There is a critical need to update the methods used in data collection in order gain a more accurate understanding. Therefore, I’ve designed a prototype sensor package, using inexpensive commercially available sensors, with the specific purpose of taking interface measurements needed in calculating surface fluxes. Due to my lack of experience and the limited availability of resources, it is unlikely that I will be able to overcome the aforementioned challenges. Therefore, my intention is to inspire more qualified scientists and engineers who are better equipped to address this area of opportunity in the future.

 

Hermann, Kiefer, Oceanography
Dr. Alison Nugent, Mentor
Rain Gauge Analysis of Precipitation on Oahu

Precipitation in Hawai’i is regulated by the incoming trade-wind flow and the topography of the islands. Farmers and meteorologists both recognize the diversity of microclimates present on each island (mokupuni). The limited land area is culturally subdivided into moku, which comprise several watersheds (ahupuaa) for community and agriculture purposes. Ancient Hawaiian farmers orally passed down experience-based knowledge of microclimate patterns on the islands for centuries, but actual observational records are not always available. Since the beginning of the 20th century, researchers have been collecting rain gauge data. Datasets are publicly available through USGS and NOAA websites. Using Matlab to analyze a few rain gauge datasets, we compare precipitation from rain gauges in different moku. We find a distinct contrast in precipitation, on the leeward and windward sides of the Ko’olau mountain range, which can be attributed to orographic processes. We expected to find similar precipitation patterns within moku, but through analysis in central Oahu we found that differences exist. Having access to actively updated precipitation records is a major foundation in outreach and educated decision making by the department of agriculture, city planners, researchers, and farmers alike.

 

Hibit, Joshua, Botany
Curt Daehler, University of Hawaii at Manoa,  Botany Dept,.
Long term decline of native remnants in an invaded Hawaiian tropical dry forest

Tropical dry forests are among the most threatened natural areas, yet relatively little is known about the impacts of anthropogenic disturbance and species introductions in these diverse biomes. In this study we revisited remnant dry forest patches that were previously surveyed in 1950 and 1970 in the Mokulēʻia Forest Reserve on Oʻahu, Hawaiʻi in order to assess long-term native persistence. We tested the hypothesis proposed by Hatheway (1952), suggesting that where disturbances by free-roaming cattle or fire were absent and natives were in sufficient abundance, native Hawaiian forests can maintain themselves, suppress alien invasion, and even expand their ranges in a broadly invaded landscape. Our resurvey of the seven original remnants found that natives declined in basal area in every plot except one, and maintained dominance over aliens in only three of seven plots. Natives experienced substantial declines in abundances, and the greatest reductions in terms of native basal area and species richness occurred in formerly well-developed native forest plots, which previously had the highest native diversity. Only the most common native species were able to maintain their populations, and these were most dominant in the rockiest plots. At the same time, non-natives increased in richness in four out of seven plots, and increased their basal area in six out of seven plots. These results indicate that despite absence of grazing cattle and fire, native Hawaiian dry forest remnants are being invaded by nearby non-natives, and will likely continue to decline if not supported by active management.

 

Ho, Lauren, Biology
Dr. Megan Porter, University of Hawaii at Manoa, Department of Biology
Erica Shin, University of Hawaii at Manoa, Department of Biology
Characterizing the 3-dimensional structure of the visual system in the copepod, Labidocera madurae

The copepod, Labidocera madurae, is a crustacean that plays a significant role in the oceanic ecosystem, however very little is known about the physical structure and complexity of the copepod eye.  Due to differences between female and male L. madurae visual systems, which are related to mating behaviors, I am looking to characterize the 3-D structure of the eyes in both sexes. The ventral eyes are primarily used for light reception while the dorsal eyes are responsible for prey detection and mating rituals.  The goal of this project is to create a 3-D rendering of the copepod visual system using 3-D analysis software and confocal microscopy.  It is hypothesized that when the visual structure of the L. madurae is observed, there will be differences between the eye structure of females and males regarding only the dorsal eye and not the ventral eye.  By examining and identifying these differences, we will gain insight regarding the ecology and interactions of L. madurae along with insight on the evolutionary structures of other marine species.

 

Huffmyer, Ariana, Hawaii Institute of Marine Biology
Ruth D. Gates, Hawaii Institute of Marine Biology
Getting a Head Start: Thermal and Nutritional Conditioning of Juvenile Corals

Thermal stress from ocean warming destabilizes the nutritional symbiosis between corals and their intracellular symbionts, leaving an energy deficit for the coral host. Corals with large energy reserves or those that can compensate for this deficit through heterotrophic feeding may have a greater chance of surviving thermal stress events. Heterotrophic nutrition plays a different role in the energetic status of corals during warm and cool seasonal periods, but little is understood on the role of cool seasonal cycles on coral growth, development, and thermal resilience. Although recent research focuses on the response of adults to bleaching events, it is unclear how post-settlement environments shape juvenile coral response to thermal stress. We evaluated the effects of conditioning regimes on the growth, survivorship, physiology, and thermal stress response of juvenile Pocillopora acuta corals. Larvae collected from parental colonies in Kāne'ohe Bay, Hawai'i were settled and exposed to cool (25.7°C) or ambient (27.3°C) temperatures either the presence or absence of a heterotrophic food source. Juveniles were conditioned in these temperature and nutritional treatments for one month before being exposed to a thermal stress test (max. temperature ca. 32°C). There was a positive effect of cool temperature on survivorship and a positive effect of heterotrophic nutrition on growth. Cooler temperatures and heterotrophic nutrition also increased tissue thickness, symbiont densities, and thermal resilience, indicating that these conditions shape physiological responses in warming conditions. These results suggest that cool seasonal periods and heterotrophic feeding enhances resilience of juvenile corals to elevated temperatures and bleaching events.

 

Hurley, Kaleonani, Biology
Robert Toonen, HIMB, UH Manoa
Crabbing and Connectivity: science for sustainability

Hawaiian fishponds, or loko iʻa, are ancient aquaculture systems that are models of sustainable aquatic resource management based on long-term experience from traditional Native Hawaiian havest practices.  An estimated 350+ fishponds provided food security for ancient Hawaiʻi, but by 1901 only 99 remained in production, and most of those were abandoned by mid century. Reclamation efforts, beginning in the 1970s, have resulted in the rejuvination of 38 actively managed fishponds across the State.  Fishponds are being adapted to modern human population needs, because functional fishponds contribute to improved food security.  In this study, we seek to examine culturally and economically important crab fishery species to ask two primary questions: 1) Are fishponds self-seeding or well-connected to the surrounding coastal waters, and 2) What are the traditional management practices for our species, and can those still work today?  To find whether fishponds are self-seeding, we will use genetic sequence data to estimate fine-scale patterns of dispersal and exchange between fishponds, adjacent coastal waters, and nearby islands for each of these species. In order to address merging traditional and modern management practices, we investigate traditional fishing and combine it with modern collection data to propose a sustainable crab fishery model.

 

Jimenez, Winter, GES
Assessing the Status of the Reef at Baker and Howland Islands

Baker and Howland Islands are located in the Central Pacific and preserve some of the most pristine coral reef ecosystems. Due to the remote location, the islands have had minimal contact from anthropogenic activity, but they are still under threat. Surveys conducted by the Ecosystem Sciences Division of the National Oceanic Atmospheric Administration Pacific Islands Fisheries Science Center indicate that benthic composition and structure vary across space and time. Baker and Howland experienced a coral bleaching event following the 2009-2010 El Niño Southern Oscillation event that resulted in increased sea surface temperatures. This study has looked at the coral reef community structure for the years 2012, 2015, and 2017 to assess any change in abundance and spatial distribution of the main benthic taxa in order to provide a general overview of the current status of the islands and how they have changed since the first documentation in 2012. Three different depth strata were used to understand the composition of both the forereef and reef shelf sites. The main functional groups focused on in this study are coral, coralline algae, and macro algae. Benthic composition changes with depth, as some species thrive with more sunlight while others can survive at lower light levels. The results of this study will determine how the benthic cover of the reef has changed in the past eight years, therefore giving insight on how the reef might change in the future if sea surface temperatures and widespread bleaching continue to occur.

 

Jiyarom, Boonyanudh, Molecular and Cell Biology
Daniel P. Strange, Department of Tropical Medicine, Medical Microbiology and Pharmacology Dr. Saguna Verma, Department of Tropical Medicine, Medical Microbiology and Pharmacology
Axl receptor promotes Zika virus infection of human Sertoli cells

Zika virus (ZIKV) is an arbovirus belonging to the Flavivirus genus of the Flaviviridae family. During the 2015-16 epidemic ZIKV emerged as sexually transmitted virus, an unexpected finding not reported for other mosquito-borne flaviviruses. The detection of ZIKV in semen and sperm for months after symptoms onset indicates the virus establishes persistent infection in the testes. Our recent work shows that human Sertoli cells (hSeC) support robust ZIKV replication for up to 9 days post-infection without compromising cell survival. In contrast, we found that human Leydig cells (hLC), another important cell type of the testes responsible for producing testosterone, does not support productive ZIKV infection. Collectively, this suggests that ZIKV has a distinct tropism for different testes cell types. Numerous reports have identified Axl, a TAM (Tyro3, Axl, Mer) receptor tyrosine kinase, as a potential entry factor for ZIKV. Published data indicates that the Axl receptor is highly expressed in hSeC whereas hLC is shown to exhibit low Axl expression. Our objective here was to test the effect of blocking Axl on ZIKV infection of hSeC. Pre-incubation of hSeC with an anti-Axl antibody that blocks ligand binding of Axl or with the Axl-specific kinase inhibitor R428 prior to ZIKV infection significantly reduces ZIKV titers in hSeC by 24 hours post-infection. Furthermore, we observed a dramatic decrease in type I interferon response in R428 treated hSeC infected with ZIKV at 24 and 72 hours post-infection. Taken together, this indicates that Axl promotes ZIKV infection in hSeC and that Axl expression may be determining factor for testes cell tropism.

 

Johnston, Erika, Marine Biology
Zac Forsman, Hawai`i Institute of Marine Biology, University of Hawai`i at Manoa
Robert Toonen, Hawai`i Institute of Marine Biology, University of Hawai`i at Manoa
A rapid molecular assay to differentiate Pocillopora corals in Hawaii

Species within the scleractinian genus Pocillopora Lamarck 1816 exhibit extreme phenotypic plasticity, making identification based on morphology difficult. However, the mitochondrial open reading frame (mtORF) marker provides a useful genetic tool for identification of most species in this genus, with a notable exception of P. eydouxi and P. meandrina. Based on recent genomic work, we present a quick and simple, gel-based restriction fragment length polymorphism (RFLP) method for the identification of all six Pocillopora species occurring in Hawai`i by amplifying either the mtORF region, a newly discovered histone region, or both, and then using the restriction enzymes targeting diagnostic sequences we unambiguously identify each species. Using this approach, we documented frequent misidentification of Pocillopora species based on colony morphology. We found that P. acuta colonies are frequently mistakenly identified as P. damicornis in Kane`ohe Bay, O`ahu. We also found that P. meandrina likely has a northern range limit in the Northwest Hawaiian Islands, above which P. ligulata was regularly mistaken for P. meandrina.

 

Jones, Ryan, Zoology
Erik Brush, The University of Hawaii at Mānoa, Biology
Resource Partitioning in Congeneric Lizardfishes

Resource partitioning occurs when ecologically similar species exhibit differences in resource use, perhaps due to present or past competition.  We observed and collected three species of lizardfish (Synodus dermatogenys, S. ulae, and S. variegatus) on the south and west shores of O‘ahu to determine whether these species partition their use of space and/or food.  For each lizardfish observed by SCUBA divers, we assessed environmental variables (depth, microhabitat, and reef area), visually identified individuals to species, estimated total length, and captured some fish for dietary analyses. The few visually identifiable prey confirmed previous accounts of Hawaiian lizardfishes as feeding generally on a variety of fish and shrimp, including one instance of cannibalism. Habitat observations revealed that some spatial partitioning does occur among the three species. S. dermatogenys were most frequently found on sand or rubble off of continuous reefs. In contrast, S. variegatus and S. ulae most often occurred on hard substrates on continuous reefs or their margins, though have previously been shown to have different depth ranges.  We conclude that the latter two species would be most likely to compete with each other within shallow environments.

 

Kelly, William, Global Environmental Science
Petroleum Refinery Wastewater Treatment

Current practices regarding the treatment of petroleum refinery wastewater rely on high energy usage and the effluent maintains high nutrient levels. Post treatment, the water is discharged into local waterways. The high nutrient levels may lead to eutrophication in surrounding waters, thereby making the treatment process an environmentally, socially and economically damaging process. Both the high energy demand and elevated nutrient levels in the effluent, are reasons to explore new methods to treat the petroleum refinery wastewater and find a more sustainable way of doing so. While the majority of the petroleum industry treats their wastewater mechanically and chemically, some utilize artificial wetlands. This is a low energy process that produces effluent with very low nutrient levels. The sustainability of a process can be calculated using metrics within the three pillars of sustainability - economic, environmental and social. Each category carries equal weight and will provide a complete understanding of the processes impact. Balancing the most benefit within the three categories will ensure the most sustainable process is understood. In this study, life cycle analysis’ will be conducted on both treatment types to better understand the complete environmental, social and economic effects of them. In weighing both processes, the goal is to provide data to inform the petroleum industry of the most sustainable process. Satisfying the three pillars of sustainability – economical, environmental and social – will provide enough benefit to interested parties to potentially change their processes.

 

Kennedy-Gold, Stevie, Biology
Amber N. Wright, University of Hawaiʻi at Mānoa
Determining the Effects of Community Composition on Behaviors and Time Budgets of Introduced Lizards in Hawaiʻi

Introductions of the green anole Anolis carolinensis and the Cuban brown anole Anolis sagrei to the Hawaiian Islands has provided a unique opportunity to determine the influence of community composition on behavior and of behavior on competition. Previous work has documented the phenomenon of resource use shifts when these lizard species interact, but little work has documented the role and significance of behavioral interference in driving competition in the field. To elucidate the role of behavior in mediating species interactions in this system, we used focal animal sampling techniques to film the behaviors of lizards in semi-natural experimental mesocosms containing either one species (A. carolinensis or A. sagrei) or both species (A. carolinensis and A. sagrei). Videos were reviewed and scored using the software JWatcher. The resulting output of durations and frequencies for each behavior was used to create time budgets, a record of how much time an organism allocates to different activities. Through comparison of A. carolinensis’ time budget when in allopatry to its time budget when sympatric with A. sagrei, and vice versa, we are exploring whether interference (i.e., aggression between species) occurs, and whether either species alters their time budget in response to competition. Preliminary results indicate that aggressive interference is not a mechanism driving competition in this system as no interspecific aggression has been observed to date. More subtle shifts in time budgets, such as reduced display or foraging activity, may therefore play a role in this interaction.

 

Kraft, Derek, Marine Biology
Melanie Hutchinson, NOAA and Hawai'i Institute of Marine Biology
Brian Bowen, Hawai'i Institute of Marine Biology
Global Genetic Inventory of the Silky Shark (Carcharhinus falciformis), the Shark Finning Industry, and DNA Fingerprinting

Silky sharks (Carcharhinus falciformis) occur in all oceans and are the second highest elasmobranch harvest on the planet. Their habitat overlaps with commercial tuna fisheries, and account for over 90% of the shark bycatch in tropical purse seines. Silky sharks are also one of the most exploited species in the shark fin trade. As a result, this formerly abundant species has declined by more than 85% in the last 20 years and is now listed as Near-Threatened and Declining by IUCN. Despite this dramatic population crash, there is little information on genetic stock structure to identify the basic units of wildlife management. This project provides a global genetic inventory with 657 specimens from 12 globally distributed locations. Using restriction site-associated DNA polymorphisms (ezRAD) in whole genome scans, 16,000 single nucleotide polymorphisms (SNPs) were identified to calculate population structure. We show distinct genetic differences between Indo-Pacific, Red Sea, and Atlantic populations and low levels of population structure between Atlantic regions. A comparison of the maternally inherited mitochondrial genome to the nuclear genome indicates female philopatry and male mediated dispersal across ocean basins. Finally, we are using this global genetic inventory as a baseline to identify the origins of Silky sharks in the fin markets. Over 1000 specimens from the fin market in Hong Kong, China will be compared to our global baseline. This will allow the identification of sharks in the fin trade to both the species-level and oceanic region of origin, providing a much-needed scientific foundation for management plans.

 

Lactaoen, Kimberly, Biology
Chantell Balaan, JABSOM, UH Manoa
Jimmy Nguyen, Dept. Biology, Uh Manoa
Masato Yoshizawa, Dept. Biology, UH Manoa
Genetic correlation between core autism-like behaviors in an emerging teleost genetic model.

Autism spectrum disorder (ASD) is diagnosed in 1-2% of the population, yet its complex mechanism obstructs effective therapy. Good approaches to unravel ASD is to have a proxy genetic model, which (i) overlaps the molecular and neural pathways of humans and (ii) shows a set of behaviors similar to core ASD symptoms. Such a model could highlight ASD’s core etiology. The Mexican tetra, Astyanax mexicanus, which is composed of cave-dwelling and surface-dwelling forms, substantially fill these aspects: cave-forms exhibit less-socialness, imbalanced attention, sleep-loss, hyperactivity, repetitive behavior and high anxiety hormone levels than surface forms. Our former bioinformatics, pharmacological and diet-treatment studies, showed that these two forms are useful to provide experimental approaches that link the nervous system, immune system, metabolism, and gut microbiota as ‘the core mechanisms’ for ASD-like symptoms shared between cavefish and humans. Here we are determining the genetic correlation among ASD-like behaviors. Since cave and surface forms are interfertile, we are rearing ~670 F2 intercross individuals to gain enough statistical power to detect ≧ 2.8% of phenotypic variance. We are currently assaying imbalanced attention (i.e. attraction to a particular frequency of water oscillation), sleep-loss, hyperactivity, and repetitive turning behaviors in  F2 hybrids derived from a single pair of surface and cavefish. We have assayed 510 of 670 F2 for imbalanced attention, and 60 of 670 have been assayed for sleep-loss/hyperactivity. We are also including repetitive turning scores and are aiming to resolve genetic correlation among these behaviors. The latest update of our research project will be presented.

 

Lenz, Elizabeth, Marine Biology
Ruth D. Gates, Hawaiʻi Institute of Marine Biology
Effects of differential bleaching response in a reef-building coral on reproductive capacity and offspring performance

As coral bleaching events continue more frequent and intense, it is imperative to monitor the impacts on key ecological proceses that promote coral recovery and resilience.  During the 2014 and 2015 bleaching events in Hawaiʻi Montipora capitata, a the dominant reef-building coral in Kāneʻohe Bay, Oʻahu displayed contrasting bleaching responses with colonies side-by-side completely pigmented (non-bleached) and the other white that eventually recovered (bleached).  This study tests two hypotheses, 1) reproductive capacity following the bleaching events would differ between bleached and non-bleached colonies and 2) intentionally crossing gametes based on parental bleaching history would affect offspring performance.  Following the bleaching event in 2016 and 2017, total reproductive output, egg size, and eggs per bundle were measued and only in 2016 were offspring produced from four types of crosses based on parental bleaching history.  While there were no significant differences in total reproductive output, egg size, or the number of eggs packaged per bundle between the two parental types, fertilization, settlement and spat survivorship was highest in offspring from either only mothers or parents that had not bleached at all.   M. capitata continues to demonstrate reproductive resilience despite recent consecutive bleaching events; however, colonies that are resistant to bleaching may be favored by selection.

 

Lenz, Elizabeth, HIMB
Ruth D. Gates, Hawaii Institute of Marine Biology
Co-Parenting Coral for Success:
Testing the Ability to Elicit Thermal Tolerance in the Next Generation

Coral bleaching in response to El Niño events and rising sea temperatures has contributed to the degradation of coral-reef ecosystems and has become an international concern. As the unprecedented rate of increasing temperature continues to threaten coral-reef ecosystems, studies testing the efficacy of coral assisted evolution to enhance thermal acclimatization and adaptation in reef-building corals has only recently began. The purpose of this study is to test parental effects in the reef-building coral Montipora capitata, specifically, testing the ability to enhance thermal tolerance through selective breeding based on parental traits and temperature conditioning. 20 M. capitata colonies in Kāneʻeohe Bay, Oʻahu were selected as parental colonies based on their response to the 2015 bleaching event (bleached vs. nonbleached) and Symbiodinium clade (Clade C dominance vs Clade C and D mixture). Prior to spermatogenesis and vertical transmission of Symbiodinium from the parent to the eggs, colonies will be conditioned under high and control temperature treatments that reflect bleaching and non-bleaching years in Kāneʻohe Bay, respectively. The impact of temperature on parental colonies will be assessed by measuring growth, photophysiology, reproductive output and gamete quality. During the spawning season, fertilization and larval performance (survivorship, respiration, and settlement) will be measured in offspring selectively bred from parents based on their bleaching history and temperature treatment. This study will determine the capacity for M. capitata to increase thermal tolerance through intergenerational acclimatization.  Furthermore, this study aims to inform coral-reef restoration and conservation on effective practices in sexual propagation as oceans continue to warm.

 

Lewis, Claire, Biology
Amy L Moran, University of Hawaii at Manoa
Tayler Massey , University of Hawaii at Manoa
Shayle B Matsuda, University of Hawaii at Manoa
Zac H Forsman, University of Hawaii at Manoa
Dave Gulko, Division of Aquatic Resources
Peter B Marko, University of Hawaii at Manoa
Phenotypic plasticity in the stress-tolerant coral Pavona varians

Coral reefs are rapidly changing in response to multiple anthropogenic stressors. While the majority of reef-building corals are declining, some genera, capable of tolerating warm and turbid environments,  are bucking this trend and increasing in abundance. Among these apparent winners, Pavona varians is a morphologically variable habitat-generalist. Increases in relative abundance of species like P. varians could be caused by a high capacity to adapt, acclimatize, or both. Field observations indicate that some of the morphological variation in P. varians appears to be adaptive in response to light, e.g. flat platy colonies in low light, and semi-massive ridged colonies in the sun. To test the extent of plasticity, we experimentally investigated light’s effect on growth and morphology of P. varians. We fragmented four genotypes and grew clones in four replicates of full sunlight, 2x layers, or 4x of 50% shade cloth in a flow-through sea water, at the Department for Aquatic Resources Ānuenue Facility at Sand Island. Colonies were weighed, and photographed monthly, and after 6 months multiple photographs per colony were used to create 3D photomodels. Growth rates, tissue thickness, and lipid content were all maximized at the lowest light level, but colonies also altered their morphology in response to light: taller ridges and fewer corallites in high light, smoother surfaces and more corallites in low light.  Our results suggest plasticity and ability to grow in reduced light environments could explain the increase in abundance of P. varians in the face of increasingly marginal conditions.

 

Lewis, McKenna, Oceanography
Craig Smith, University of Hawai'i at Manoa
Maria Vernet, Scripps Institution of Oceanography
Andrew Sweetman, Heriot-Watt University
Clifton Nunnally, University of Hawai'i at Manoa
Down-fjord changes in macrobenthos in glacially influenced Andvord Bay, Antarctica

Glaciomarine fjords exhibit substantially different ecosystem forcing than adjacent continental shelves and can be highly sensitive to climate warming. Extensive research indicates that subpolar Arctic fjords are heavily influenced by glacial meltwater and sediment inputs, resulting in high turbidity and seafloor burial rates. These physical disturbances yield macrofaunal communities with low abundance and diversity. In contrast, poorly-studied sub-polar fjords along the Western Antarctic Peninsula (WAP) sustain weak meltwater influences, resulting in low turbidity and seafloor burial rates. Thus, benthic communities in WAP fjords may not currently be limited by turbidity and burial disturbance and may have the potential to harbor abundant and diverse macrobenthic communities. Here we characterize the benthic macrofaunal community of Andvord Bay, a subpolar fjord along the warming WAP. We compare down-fjord changes in macrobenthic abundance, diversity, and functional-group structure (groups of organisms with different ecosystem roles) to a variety of potential ecological drivers. These ecological drivers include sediment burial rate, sediment Chl-a concentration (an indicator of labile detritus availability), and sediment-community respiration (an indicator of seafloor detrital carbon flux).  Benthic abundance is high in the mid-fjord region and is most strongly correlated with carbon flux and food availability. Macrofauna abundance is high in the inner fjord regions relative to abundance in Arctic fjords in the same area. Burial disturbance may occur only within 1 kilometer of actively flowing tidewater glaciers in sub-polar Antarctic fjords. These patterns are likely to change as warming increases meltwater and sediment inputs, limiting food availability and benthic habitat.

 

Lima Fernandes, Vânia Filipa, Biology
Christian Macaspac, Department of Biology, University of Hawaii at Manoa, Hawaii, USA
Louise Lu, Department of Biology, University of Hawaii at Manoa, Hawaii, USA
Masato Yoshizawa, Department of Biology, University of Hawaii at Manoa, Hawaii, USA
Evolutionary emergence of the laterality in between mechanosensory lateral line and its associated adaptive behavior of the Mexican blind cavefish

Many animal species exhibit laterality in sensation and behavioral responses, namely, the preference for using either the left or right side of the sensory system.  However, it is largely unknown whether such laterality in sensory-behavior coupling evolves during rapid adaptation processes. A cave form of the Mexican tetra, Astyanax mexicanus, evolved from surface-dwelling ancestors and rapidly adapted to cave by enhancing traits including vibration attraction behavior (VAB), an adaptive foraging behavior in darkness, and its underlying mechanosensor, superficial neuromasts (SN). The SN enhancement is promoted by the budding of neuromasts, which is, in zebrafish and medaka, encouraged by the underneath dermal bone formation. In the present study, we inhibited the endothelin signaling, which is a major known regulator for dermal bone formation, in juvenile fish (from 1 to 3 months-old) via endothelin inhibitors. The endothelin-signaling inhibition increased the cranial SN in both surface and cavefish and also increased the dermal bone formation in cavefish, however, bone enhancement was observed in the much later stage than that of SN, suggesting that the endothelin signaling may independently regulate the SN increase and the bone formation in cavefish. Surprisingly, the left side-SN increase regardless of by the normal development or by inhibitor treatment, was positively correlated with VAB in cavefish. the association with right side-SN, or laterality in surface fish was not observed, suggesting the laterality between left SN and VAB may have evolved during adaptation to cave. Accordingly, cavefish emerged as a useful model to investigate the evolution of laterality.

 

Martinez-Sepulveda, Michael, TPSS
Dr. Kenneth W. Leonhardt, Principle Investigator
Inducing Polyploidy in Erythrina variegata as a Gall Wasp Management Strategy

Erythrina variegata ‘Tropic Coral’ was the preferred windbreak in Hawaii until an invasive pest, the Erythrina Gall Wasp, destroyed almost all these plants in the state.

The variety Tropic Coral, as a windbreak, was only a memory until serendipity struck in a polyploidy experiment. Polyploidy is the state of extra chromosomes sets in cells, something plants tolerate well. In a different project in 2009, Leonhardt & Shi induced polyploidy in many plants because polyploids are often sterile and do not produce seed litter. The E. variegata plants from this project were not sterile but Dr. Leonhardt still kept them at the Waimanalo research station to observe their development.

The game changer came when gall wasps encountered the plants. The wasps destroyed some Erythrina species around these plants but some of them showed damage on <10% of their leaves. This was substantial evidence of gall wasp resistance. By inducing polyploidy to confer resistance the pest, the reintroduction of Hawaii’s preferred windbreak is now possible.

My master’s project focuses on understanding this resistance and preparing polyploids of E. variegata to be restored to former locations of growth. Reintroduced plants will continue to provide benefits long after my degree is earned. Once a small population is well established, cuttings can be generated easily and indefinitely. Therefore, when completed, this project will be self-sustaining. Growers of all scales, from the mega production size to the ½ acre family farm, will again have this plant available as a windbreak.

 

Matsuda, Candice, Global Environmental Science – SOEST
Dr. Jonathan Deenik
Using Soil-Water Characteristic Curves to Improve Irrigation Management

Agriculture uses about 70% of all water resources available globally which makes it the leading consumer compared to industrial and domestic use (Rosegrant, 1997). Water shortages are expected to increase as the years go on very drastically and it is predicted that by the year 2025, there will be about 56 countries that will not have an adequate amount of water considered to be water stressed (Rosegrant, 1997).  To prevent crops from dying and producing low yields, some farmers tend to add more irrigation water to their fields than is actually needed. However, this causes environmental problems including leaching of nutrients and erosion of the soil which both find a way into the ocean. This is also a problem because not all of the water added is used by the intended crop and is a waste of water. To help farmers make better decisions on their irrigation practices, it is important to understand how different soil types will hold water and the soil properties that affect the soil-water relationship. This can be done by determining a soil water characteristic curve (SWCC) for different soil types. A SWCC is a graph with pressure or suction (kPa) on the x axis and soil water content on the y axis which explains how much water a soil type will retain at differring pressures. Other soil properties that can be tested that affect a SWCC are soil texture, soil organic carbon, and soil mineralogy.

References: Rosegrant, M. W.Water resources in the twenty-first century: Challenges and implications for action. (Vol. 20). Intl Food Policy Res Inst.  (March, 1997).

 

McDonald, Marisa, Biology
Megan Porter, University of Hawaii at Manoa
Kathryn Feller, University of Cambridge
Investigating the ultrastructures in the larval eyes of stomatopod crustaceans

There is a rich history of research studying adult stomatopod crustacean visual systems, which are arguably the most complex eyes in the world. An common theme threaded throughout most of this previous work is the question of how such a complex system evolved. One strategy for addressing this question is to study the ontogeny of the visual system. Larval stomatopod eyes are physiologically and morphologically distinct from the adult eye, and are replaced during metamorphosis. Currently there is a gap in understanding of the function and development of the larval stomatopod visual system. Generally it is assumed that all pelagic larval crustaceans have  similar compound eyes with transparent apposition optics and a single photoreceptor type regardless of adult complexity. We hypothesize that the stomatopod crustacean has more complex larval eyes than previously understood. The goal of this project is to identify novel structures in the larval eyes and compare differences across species and superfamilies. Transmission electron microscopy (TEM) was used to investigate the ultrastructures of the larval stomatopod eye. TEM imaging was used to examine various structures and identify them as different or novel among species. Further studies will use physiological and behavioral methods to understand how the anatomy is related to the function and use of the larval eye.

 

McElligott, Megan, Marine Biology
Marc Lammers, NOAA Hawaiian Islands Humpback Whale National Marine Sanctuary, Oceanwide Science Institute
Investigating the ultrastructures in the larval eyes of stomatopod crustaceans

Habitat-use patterns of Hawaiian spinner dolphins (Stenella longirostris) in the Maui Nui region (Maui, Moloka‘i, Lāna‘i, and the 'Au'au channel) are poorly understood in comparison to the Kona coast of Hawai‘i Island and O‘ahu’s Wai‘anae coast. Spinner dolphins follow predictable daily behavioral cycles of nighttime offshore foraging and daytime resting in shallow bays. This daytime rest makes dolphins susceptible to human disturbance from whale watching and swim tours. In the wake of concerns over the negative impacts of human activity, the Pacific Islands Regional Office of NOAA Fisheries has proposed a 50-yard approach and swim-with limit for spinner dolphins with the potential for time-area closures. In order to detect any changes in dolphin behavioral use of the Maui Nui region due to the implementation of the rule, there must be a baseline understanding of their current use of the region. To this end, autonomous acoustic recorders were deployed in eight locations along the west Maui coast and 'Au'au channel, and one recorder was placed in a well-established resting bay off west Oahu for comparison. Recordings were quantified for dolphin acoustic activity to determine spatial, seasonal, and diel trends. The results indicate that spinner dolphins exhibit resting behaviors in the 'Au'au channel as well as nearshore areas, particularly Honolua Bay of Maui and Manele Bay of Lāna‘i. The movement of dolphins throughout the channel as they rest suggests that time-area closures likely would not benefit dolphins in Maui Nui, and the 50-yard approach limit would be a more effective option.

 

McGowan, Ashley, Hawai'i Institute of Marine Biology
Keisha D. Bahr, University of Hawaiʻi at Mānoa, Hawaiʻi Institute of Marine Biology
Ridge to reef connections: effects of invasive mangrove removal on nearshore coral reef environment

The Heʻeia watershed has been severely impacted by invasive species, such as California grass (Urochloa mutica) and red mangroves (Rhizophora mangle). Currently, removal of these invasive species and replanting of native riparian plants is underway, with expected widespread changes from the terrestrial ecosystem to the tightly linked coastal environment directly downstream. To understand the impacts of such restoration activities on the adjacent coral reef environment, we established 24 long-term monitoring sites where we assess fish populations, sedimentation levels, water quality, and coral reef health. This project integrates traditional and contemporary research and monitoring strategies to understand the effects of land restoration activities on the adjacent coral reef environment. This project will identify watershed or reef management actions that can improve the health of the nearshore coral reef. The marine ecosystem data collected will integrate with the freshwater, fishpond, and terrestrial components to allow for an ecosystem approach in understanding and managing the entire ahupuaʻa.

 

Morishige, Kanoe, Biology
Characterizing spatial and temporal variation in maternal investment of Colobocentrotus atratus

Hawaii’s intertidal ecosystems are extremely vulnerable to rising temperatures, habitat degradation, and harvesting pressure. In response to these threats, local communities are developing management strategies that support long-term health of marine resources while balancing ecological and cultural needs. This study investigates reproduction and maternal investment of a Hawaiian urchin, Colobocentrotus atratus to inform sustainable spatial/temporal harvesting strategies. At eight sites around Oʻahu and Hawaiʻi Island, we found that mothers produce smaller and more numerous eggs in the fall and fewer, larger eggs in the spring. To examine this pattern on a finer scale, urchins were collected monthly at one site (Kaʻalawai) for two years. Gonad indices were significantly different between months and there was a significant interactive effect between test diameter and month. Fecundity and egg size also showed significant differences between months, and we found evidence for two major spawning events, one in December and another in the March. Egg size decreased leading up to the December spawning event and increased leading up to the March spawning event. There was some indication of trade-off between fecundity and egg volume; however, this pattern was not as pronounced as in the inter-populational study. Physical-biological factors such as adult food availability, population size structure, temperature, and wave action may all be factors contributing to these patterns. Understanding environmental drivers of reproduction will inform local-scale management and may also shed light on potential effects of climate change.

 

McKenzie, T, Geology & Geophysics
Henrietta Dulai, Geology & Geophysics, University of Hawaiʻi at Mānoa
Brian N. Popp, Department of Geology & Geophysics, University of Hawaiʻi at Mānoa
Robert Whittier, Hawaiʻi Department of Health
Tracing groundwater pathways of wastewater using a novel approach in Kāneʻohe, Oʻahu

As reefs around the world decline due to bleaching events, research is needed to better understand coral susceptibility. Any study is complicated because differential bleaching among corals is based on intrinsic factors of the coral holobiont and environmental factors affecting assemblages. Recent work has standardized comparing responses across 317 coral taxa j, based on surveys at 316 sites k and compiled into a matrix of bleaching responses Bjk . Averaging the responses of members of a taxon over all sites k where said taxon was found, retruns a taxon-Bleaching Response Index value. Conversely, when the matrix is averaged over all taxa j found at a site, siteBjk is obtained. There is also use for a taxon specific metric that relates the bleaching response of a species to its assemblage, thus compensating for environmental factors and reflecting the intrinsic characteristics of a taxon which affects bleaching response. Taxon-alpha and taxon-beta were created by comparing how an individual taxon bleached in comparison to its assemblage. Taxon-alpha (the intercept when graphing the average of responses of all corals minus taxon j at each site k against the responses of taxon j) describes how said taxon responds to weak stresses compared to its assemblage, while taxon-beta (the slope of the same graph) describes how a taxon responds to bleaching compared to its assemblage. Many corals either over-respond to weak stress with little response to more extreme stressors or bleach little under weak stress and bleach far more than the assemblage under great stress.

 

Nalley, Eileen, HIMB
Adel Heenan, Bangor University, School of Ocean Sciences
Rob Toonen, University of Hawaiʻi at Mānoa, Hawaiʻi Institute of Marine Biology
Megan Donahue, University of Hawaiʻi at Mānoa, Hawaiʻi Institute of Marine Biology
Functional homogenization of herbivorous coral reef fishes across the Pacific

Complementarity and specialization are critical facets of biological diversity that influence ecosystem function and resilience on coral reefs. Habitat degradation and biodiversity loss resulting from human impacts can lead to functional homogenization, whereby natural communities become less specialized and distinct. Herbivorous reef fishes display different degrees of specialization, and make an excellent model for assessing functional homogenization in human influenced communities. Modifying an approach used in terrestrial systems, we generated a reef fish specialization index (ASI – Assemblage Specialization Index) to explore the relationship between humans and the relative abundance of specialists. We combined species-level diet data from existing literature and abundance data to generate a measure of specialization for nearly 4000 sites throughout the Pacific. Using this large-scale dataset encompassing a spectrum of intact to degraded coral reefs, we modeled the impact of humans on the herbivore ASI, relative to habitat and biophysical drivers. In hierarchical models examining the response of specialization to a suite of environmental and anthropogenic drivers, we found a strong positive relationship between specialization and total herbivore biomass, richness, and diversity. Human population had little direct relationship with ASI but may have indirect impacts. As coral reefs face mounting stressors it is especially important that we apply novel methods to examine subtle ecosystem change, such as the loss of specialists. Our findings suggest that humans are influencing functional homogenization in herbivorous reef fish assemblages throughout the Pacific in complex ways.

 

Nichols, Patrick, Marine Biology
Dr. Peter Marko, UHM

Coral reefs support the most diverse assemblages of marine life on Earth, yet their biodiversity is declining due to local and global stressors. The rapid assessment of coral reefs, which traditionally relies on visual and photographic estimates of coral cover, or the percentage of substrate occupied by living scleractinian corals, requires regular and cost-effective monitoring for targeting conservation efforts. The analysis of environmental DNA (eDNA) is a relatively new technique that has the potential to offer fast and efficient insights into the abundance and distribution of species, yet it remains untested in corals. Here, we demonstrate how targeted PCR amplification and metabarcoding of coral DNA from seawater samples can be used to estimate percent cover of corals. Our data showed that visual estimates of coral cover are highly correlated with eDNA estimates of coral biomass on natural reefs in Hawai’i. Given its high sensitivity, relatively low cost, and broad applicability, coral assessments with eDNA can provide complementary analytical support for biomonitoring programs tracking rapid changes in the impacts of climate change, overfishing, and management initiatives.

 

Niimi, Yuuki, Marine Biology
Jeffrey C. Drazen, Department of Oceanography
How does mesopelagic micronekton community structure change near the Central Equatorial Pacific?

The deep-sea, typically considered the oceans below 200m, is the largest habitat on Earth. The upper portion (200 - 1,000 m) of the open waters of the deep-sea is called the mesopelagic region. The ecosystem is ecologically distinct since most animals vertically migrate from the depth during the day to the surface at night. The mesopelagic micronekton are critical in food webs, functioning as intermediates between lower trophic levels and top predators. Additionally, these animals provide food to commercially exploited fish such as tuna and swordfish, which feed at varying depths throughout the mesopelagic. Though the vertical structure of the mesopelagic community has been investigated around Hawaiʻi and in other parts of the Pacific Ocean, there currently are not any evaluations of this community in the dynamic equatorial region. Here we look at the quantitative abundance, biomass, and the vertical structure of the communities between 5o and 8o North. The difference in the latitude will provide a comparative study system, as the lower latitude location will experience a stronger effect on equatorial upwelling. Mesopelagic micronekton at the two sites were collected from a Multiple Opening Closing Net Environmental Sampling System (MOCNESS) which separates the samples into different depth layers and monitors the volume of the ocean to provide quantitative vertical structure. This study will provide important information for fishery managers to understand how mesopelagic micronekton, the food source for many commercially important species, are latitudinally affected by the equator.

 

Opalek, Mariah, Marine Biology
Matsuda, Shayle, Hawaii Institute of Marine Biology
Gates, Ruth, Hawaii Institute of Marine Biology
Cunning, Ross, Rosensteil School of Marine and Atmospheric Science
Ritson-Williams, Raphael, California Academy of Sciences
The differential effects of Symbiodinium type, coral color and light intensity on growth in the coral species, Montipora capitata

Coral bleaching is a widely known and devastating phenomenon affecting the health of coral species. However, other factors such as growth can be a determining factor for life or death in a competitive reef environment. Montipora capitata is a dominant reef-building coral species found in Kane‘ohe Bay, O‘ahu. They rely on their algal endosymbiont partners, Symbiodinium, that through photosynthesis generate nutrients needed for coral growth. Colonies of Montipora capitata in Kane‘ohe bay are either brown or orange in color and associate with Symbiodinium in clades C or D. Here we investigate how Symbiodinium type and coral color influence coral growth at different light environments (% irradiance). Coral fragments (<5cm) were collected from Reef 13 at depths of 2-3m from tagged parent colonies with a known history of being clade C brown (79 fragments), clade C orange (66 fragments) or clade D orange (70 fragments). The coral fragments were divided into four different light exposures using shade cloth: 100% (control) and reductions to 75%, 25% and 5%.  Growth was measured by buoyant weighing the fragments every four weeks for three months. Preliminary evidence shows that the dominant Symbiodinium type plays a larger role influencing coral growth in Montipora capitata (C > D) when light exposure is high. However, there is no significant difference in growth due to clade type in treatments with low light. Understanding how Symbiodinium effects coral growth in different light environments can help us understand how corals will respond (or recover) in different locations on the reef during stress events.

 

Ortega, Egle, Anatomy, Biochemistry, and Physiology
Quinci Salvador, Institute for Biogenesis Research, Department of Anatomy, Biochemistry and Physiology, John A. Burns School of Medicine, University of Hawaii at Manoa
Mayumi Fernandez, Institute for Biogenesis Research, Department of Anatomy, Biochemistry and Physiology, John A. Burns School of Medicine, University of Hawaii at Manoa
Monika A. Ward, Institute for Biogenesis Research, Department of Anatomy, Biochemistry and Physiology, John A. Burns School of Medicine, University of Hawaii at Manoa
Alterations of gonadal development in males with limited Y chromosome genes

Y chromosome is required for testicular development and male fertility. Previously, we demonstrated that only two Y-encoded genes are needed for successful assisted reproduction in the mouse: testis determinant Sry and spermatogonial proliferation factor Eif2s3y. Subsequently, we showed that function of these genes can be replaced by transgenic overexpression of their homologues, Sox9 and Eif2s3x. Males with 2 (XEif2s3yOSry), 1 (XEif2s3yOSox9 and XOSry,Eif2s3x) and no (XOSox9,Eif2s3x) Y genes produced haploid gametes and sired offspring after round spermatid injection (ROSI) despite varying degrees of testicular pathologies. We hypothesized that observed gonadal abnormalities originated from altered signaling at the time of sex determination. To test this hypothesis we assessed development of genital ridges (gonadal precursor) in the same males at 12.5 dpc (days post coitum) focusing on their morphology and transcriptional profile of sex determination pathway. Morphometric analyses revealed that all transgenic males had feminized gonadal shape, impaired development of testis cords, and altered gonadal vasculature. Factors promoting male pathway (Fgf9 and Amh) were downregulated in all transgenic males compared to XY. Sry-to-Sox9 substitution in the context of Eif2s3x and Eif2s3y-to-Eif2s3x substitution in the context of Sry had no effects. However, Sry-to-Sox9 substitution in the context of Eif2s3y and Eif2s3y-to-Eif2s3x substitution in the context of Sox9 resulted in altered Fgf9 and Amh levels. Sex determination driven by Sox9 overexpression resulted in upregulation of female pathway factors (FoxL2 and Rspo4). This work advances the understanding of the roles of Y chromosome genes and their homologues during sex determination in the mouse. Funded by NIH HD072380 to MAW.

 

Oyafuso, Zack, Marine Biology
PingSun Leung, University of Hawaii at Manoa, Department of Natural Resources and Environmental Management
Erik C. Franklin, Hawaii Institute of Marine Biology, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa
Evaluating Bioeconomic Tradeoffs of Current Fishing Reserves Via Spatial Optimization

No-take marine reserves are common strategies used in spatial fisheries management. There are at least four general objectives for marine design: (1) maximizing conservation, (2) minimizing total reserve area, (3) maximizing reserve compactness, and (4) minimizing socioeconomic opportunity cost. Through spatial optimization, we evaluated the bioeconomic tradeoffs and potential gaps of a subset of current bottomfish restricted fishing areas (BRFAs) for the Hawaiian deepwater bottomfish fishery. Model-based species distribution maps were used as conservation features of the optimization. Opportunity cost, the potential socioeconomic impact of reserve closure, was defined as bottomfish revenue. Optimized reserve placements with minimal opportunity costs had little overlap (< 5%) with the current placements of the BRFAs. The opportunity cost of the optimized reserve placements was 50-75% less than that of the current BRFAs but provided 30-40% higher potential conservation value. When optimized reserve placements were designed to provide a maximal opportunity cost there was up to a 31.5% overlap with the current BRFAs, highlighting a potential drawback of the current BRFA system with respect to socioeconomic impacts. When opportunity cost was instead calculated as total area, the optimized placements had some overlap with the current BRFAs, and the placements were similar to the cost-minimization and cost-maximization placements when the opportunity cost was calculated as revenue, highlighting the importance of socioeconomic data to the reserve design process. This analysis emphasized the use of spatial optimization to not only guide the reserve design process, but to highlight tradeoffs of conflicting fisheries objectives in reserve design.

 

Palecanda, Sitara, Biology
Megan Porter, University of Hawai'i at Mānoa
Ultraviolet Opsin Diversity in Stomatopods

Stomatopods (Crustacea, Stomatopoda), are well known for their aggressive behavior, hunting style, and their unique visual system. Their stalked eyes move independently and have multiple spectral and polarization channels, with some species possessing up to 16 spectrally unique photoreceptors and expressing 33 different visual opsin proteins as adults. The retina of larval stomatopods by contrast are thought to be less complex, lacking photoreceptor diversity. During the last larval stage, the adult stomatopod retina is formed alongside the larval retina that then degrades as the adult retina develops. Ultraviolet (UV) sensitive opsins have been found in several adult stomatopods and are particularly common in those species that live in shallow waters where UV light is plentiful. Interestingly, UV sensitive opsins have also been found in larval stomatopods of several species though the cellular structures responsible for UV sensitivity in adults were not previously thought to exist in the simple larval eye. It is unknown what ecological role UV light detection serves for larval stomatopods. A molecular survey of stomatopod UV opsins will be conducted using transcriptomic data from embryonic, larval, and adult stomatopods across described superfamilies in order to identify conserved regions in the amino acid sequence that may be related to specific wavelength sensitivity. This, combined with expression data, will provide more information about the differences between larval and adult stomatopod vision.

 

Papacek, Katherine, Global Environmental Science
Kirsten Leong, Social Scientist for the National Oceanic and Atmospheric Administration Michael Guidry, Undergraduate Chair for the Oceanography Department at the University of Hawai'i at Manoa
The Media’s Portrayal of Offshore Aquaculture in the Pacific and How it Affects the Public Perception of the Aquaculture Industry

As the aquaculture industry continues to develop, the National Oceanic and Atmospheric Administration is attempting to define national regulations for offshore aquaculture in U.S. federal waters in the Pacific Islands Region. These regulations may have a variety of implications for nearby United States and U.S. territories, including the islands of Hawaii, Guam, American Samoa, and the Commonwealth of the Northern Mariana Islands. However, for many individuals living in this region, it is still unclear whether the potential benefits of aquaculture production outweigh the environmental and socio-economic risks. To gain insight on the public’s perception of the aquaculture industry and improve future communications, this study conducted a content analysis of regional newspaper articles pertaining to offshore finfish aquaculture in the Pacific Ocean from 2000-2017. This outlet of communication was chosen because media coverage is often an important source of information for consumers and the general public. Public scoping comments from NOAA’s Programmatic Environmental Impact Statement were also evaluated. Articles were coded for themes related to topics discussed (e.g., risks and benefits of offshore aquaculture), tone (e.g., positive, negative), and sources referenced. Key findings include an evaluation of the frequency of themes portrayed throughout the media as well as an in-depth analysis of public or stakeholder opinion of offshore aquaculture. The overall intent of this research and the subsequent recommendations is to provide insights that may contribute to strengthening policy decisions for fin-fish aquaculture throughout the Western Pacific.

 

Payne, Courtney, NREM
MANAGING INVASIVE MACROALGAE IN PAIKŌ LAGOON STATE WILDLIFE SANCTUARY: A PARTNERSHIP WITH THE STATE OF HAWAI‘I AND THE MAUNALUA COMMUNITY

Invasive macroalgae negatively affects marine areas by monopolizing space, altering geochemistry, and changing food webs. Hawaii’s Division of Forestry and Wildlife (DOFAW) seeks to establish an official protocol for managing invasive macroalgae in Paikō Lagoon State Wildlife Sanctuary as part of their larger efforts to manage sites throughout O‘ahu. This capstone project developed a long-term, volunteer-based invasive macroalgae removal and monitoring program as a practical solution for the DOFAW staff. I developed removal protocols based on an understanding of the macroalgae biology, lessons learned from past efforts, removal practices outlined in the current literature, and observations of other group’s removal process. I developed monitoring protocols guided by the work of Lindenmayer and Likens to measure long-term macroalgae conditions. Final protocols include groups of four volunteers using quadrats, five-gallon buckets, and hand nets to remove only invasive macroalgae in set transects and subsections. A pilot, nine-month monitoring period revealed significant decline in average percent cover in the transect with the most removal events (77% (95% CI [±18.27]) to 31% (95% CI [±16.53])). The benefits of these protocols include reduction of invasive macroalgae, deployment using minimum budget and staff resources, and community engagement in natural resource management and ecological field methods.

 

Pejhanmehr, Mersedeh, Botany
Mitsuko Yorkstone, Botany
Population Genetics of Sida fallax in the Hawaiian Islands

Sida is a complex genus of over 100 species in family Malvaceae (the hibiscus family, tribe Malveae). Sida fallax (‘ilima) is the most variable taxon of Malvaceae in Hawaiian Islands with extensive distribution among them and extending throughout the Pacific region and into mainland China. The range of morphological and ecological variation within and among Sida fallax populations has suggested that infraspecific taxa might be recognized.

The purpose of this study was to investigate the genetic differences between various morphological forms of S. fallax in Hawaiian Islands. A minimum of 10 samples were collected from multiple populations throughout most of islands. Total genomic DNA was extracted and sequence-related amplified polymorphism (SRAP) genetic markers were used for assessing genetic diversity within and among populations.

PCR amplifications were carried out and DNA profiles were scored as a data matrix (taxa and markers) for band presence/absence. Relationships within and among populations were projected from the similarity matrixes using principal coordinate analysis (PCO) and cluster analysis with MVSP Plus ver. 3. using Gower similarity.

Several obvious differences were observed between populations. Populations of Maui Nui (Molokai and Maui) clustered together and separate from populations on other islands. In most instances, other populations reflected their island of origin. Populations from different morphological forms and found in different habitats similarly clustered by island. This suggests that different morphological forms demonstrate convergent evolution in each habitat rather than evolving once and dispersing separately to similar habitats on each island.

 

Royer, Mark, Zoology
Edward Cardona, Bangor University, School of Ocean Science
Kim Holland, Hawaiʻi Institute of Marine Biology
Carl Meyer, Hawaiʻi Institute of Marine Biology
Kelsey Maloney, University of Hawaiʻi at Mānoa
Kate Whittingham, Whitman College
Scalloped hammerhead swimming performance and thermoregulation strategies during deep dives into cold water

Adult scalloped hammerhead sharks (Sphryna lewini) utilize oceanic habitats around the Hawaiian islands where they dive repeatedly at night to depths exceeding 800m and water temperatures as low as 4°C, presumably to forage on deep-dwelling prey.  We hypothesized that S. lewini dive duration is limited by ambient water temperature at depth because body cooling associated with excursions into cold water can reduce muscle power output, cardiac function and visual acuity.   To determine how S. lewini respond to cold ambient water temperatures experienced during deep dives, we equipped adult individuals with instrument packages capable of directly measuring depth, ambient water temperature, activity rates and swimming muscle temperature.  Our specific objectives were to determine whether: (1) S. lewini maintain core body temperature during deep dives via simple thermal inertia, or instead employ active, physiological, thermoregulation, and (2) whether swimming performance changes during deep, repetitive dives into cold water. Our data suggest dive termination is triggered by slight cooling (2 to 5 degrees) of swimming muscles, and thus S. lewini are able to maintain swimming performance during their ascent to warmer surface waters.  This dive termination response is crucial because internal muscle cooling continues even after sharks return to the warm surface layer, and it takes 45 to 75 minutes for swimming muscles to fully equilibrate with ambient mixed layer water temperatures.  Understanding how S. lewini, a warm-water species, are physiologically able to exploit resources in deep, cold habitats provides important insights into the broader ecology of this regionally endangered shark.

 

Royer, Mark, Zoology
Edward Cardona, Bangor University, School of Ocean Science
Kim Holland, Hawaiʻi Institute of Marine Biology, University of Hawaiʻi at Mānoa
Carl Meyer, Hawaiʻi Institute of Marine Biology, University of Hawaiʻi at Mānoa
Kelsey Maloney, University of Hawaiʻi at Mānoa
Kate Whittingham, Whitman College
Scalloped hammerheads swim on their side with a diel shift in roll magnitude and frequency

While most sharks maintain an upright posture while swimming, it has been demonstrated that great hammerheads (Sphyrna mokarran) swim on their sides to for greater hydrodynamic efficiency by utilizing their dorsal fin as a lift-generating surface. While great hammerheads are unique amongst sharks in having a dorsal fin longer than their pectoral fins, scalloped hammerheads (Sphyrna lewini) have the next highest ratio of dorsal fin to pectoral fin lengths, which might allow for similar hydrodynamic efficiency by exhibiting the same rolling behavior. In this study we equipped adult S. lewini with multi-instrument tag packages to directly measure depth, body orientation and swimming performance. Our specific objectives were to examine whether (1) S. lewini exhibit any rolling behavior while they swim and if so, (2) examine for patterns of variation in the roll magnitude and frequency. We obtained 180 total days of data from 9 free-swimming adult S. lewini with individual deployment durations ranging from 7 to 23 days. Rolling behavior was observed in all sharks throughout their entire deployments, with each shark spending about 95% of their time swimming on their side. The degree (magnitude) and frequency of rolling showed a diel pattern. Roll angle was greater at night while the roll frequency (changing of one side to the other) was greater during the day. The observation of this behavior in another member of the Sphyrnid family provides important insights into the evolutionary context of this behavior strategy and raises interesting questions on the locomotor function of this behavior.

 

Shiesha, Ryan, Department of Biology, University of Hawai'i at Manoa
Mireille Steck, University of Hawai'i at Manoa
Larval Stomatopod Raptorial Claws – Implications for Strike Mechanics

Although the biomechanics of the famous stomatopod strike has been studied extensively in adults, information about the structure of their larval form is still very limited. In order to understand the development of these striking systems, it is necessary to analyze the morphological differences of the raptorial appendages. To do this, larval arms of stomatopods were measured using two dimensional analyses with the geomorph package in R. Two families of larval stomatopods (Squillidae and Gonodactylidae) were taxonomically identified through morphological and molecular methods. While the adult gonodactyloids exhibit smashing behavior with a bulbous dactylus, and the squilloids display spearing behavior with a sharp dactylus, larvae of both families lack the inflated dactyl heel. Further analyses will be done to describe the morphological similarities and differences of the raptorial appendages between these two groups, as well as other stomatopod families.

 

Shin, Erica, Biology
Lauren Ho, University of Hawaii at Manoa
Mireille Steck, University of Hawaii at Manoa
Identification of opsin expression in the visual system of Labidocera madurae

The copepod, Labidocera madurae, has an unusual visual system consisting of two dorsal eyes with lenses and one lensless ventral eye. Despite the unique structure of their visual system, little is known about either the eye structure or opsin expression. In order to investigate this unique yet uncharacterized visual system, molecular and cellular biology methods were utilized, including RNA extraction of near-adult stage copepods, confirmation of predicted gene sequence expression using reverse transcriptase Polymerase Chain Reaction (RT-PCR) and Sanger sequencing, and construction of DNA probes for future in situ hybridization. Previous research suggests at least six opsin genes are expressed in this species; of these, the expression of three opsin genes have been confirmed. All confirmed opsin genes are predicted to form a visual pigment with middle wavelength sensitivity(e.g. sensitive to blue light). Future work will use in situ hybridization to identify the expression patterns of these three opsins within the three distinct eyes of L. madurae.

 

Simon, Noah, Biology
Megan Porter, UH Manoa
Jason Mayberry, SUNY at Buffalo
Evolution of eye loss in parasitic batflies

Batflies are obligate ectoparasites of bats comprising the closely related families Nycteribiidae and Streblidae. These flies exhibit varying degrees of reduction of the compound eyes, including complete eye loss in many taxa, making them a valuable model for studying the evolution of eye loss. We captured images of batfly eyes using scanning electron microscopy (SEM) and used these to characterize the external morphology of the eye (eye shape, eye size, facet number, facet size). So far we have characterized the external eye morphology of ~67% of the total genera across the 2 families of batflies. We are working on constructing a batfly molecular phylogeny in order to map the morphological characters of the eyes and to analyze the evolutionary patterns of eye loss. Preliminary analyses indicate that complete eye loss has occurred at least 3 times in batflies, with high degrees of reduction present in all subfamilies.

 

Sommer, Rachel, Biology
Dr. Robert Cowie, UH Manoa PBRC
Life histories of two invasive veronicellid slugs in the Hawaiian Islands

Veronicella cubensis and Laevicaulis alte are widespread invasive slugs of the family Veroncellidae. Although they are voracious pests and are known carriers of rat lungworm, little is understood of their life histories. In order to gain more comprehensive understanding of their lives and anticipate the threats they may pose in a changing climate, a study of various life history aspects was conducted. Slugs were reared in a lab setting to gather data on lifespan reproductive trends including egg production and hatchability. The effect of temperature on juvenile growth was also determined by tracking the weight gain of slugs maintained in either a hot or cool temperature environment over the first six months of life. Although Leavicaulis alte proved difficult to maintain in lab settings, we have learned that Veronicella cubensis reaches reproductive maturity around 4 months of age, egg masses are variable in size and hatch with a high success rate, and warmer temperatures may cause faster weight gain in juveniles. This information is a crucial part of the larger picture that will help us to understand why these veronicellids are such successful invaders and to predict and prevent their further spread.

 

Souza, Mariana, Marine Biology
Spatially-skewed sex ratios and isolation in a coral population: Mechanisms for diminished or enhanced reproductive success?

As mostly sessile organisms, corals face different challenges to reproduction than those encountered by free-living organisms. Sex ratio, coral spatial distribution, and abundance can be important factors for sexual reproduction success. Fungia scutaria is a solitary coral species, which differentiates them from the majority of scleractinians. They are gonochoric, and can potentially undergo bidirectional sex change. Despite F. scutaria spawning events been annually reported in Kaneohe Bay, few to none recruits have been seen.  To investigate the spatial distribution and sex ratio of F. scutaria, 80 individuals were collected from a northern and southern reef within Kaneohe Bay (n = 40 per reef).  F. scutaria distribution differed between sites; at the northern reef, F. scutaria was present in high number in patches inside holes, while in the southern reef F. scutaria was randomly distributed across the reef. During the 2017 spawning, sex was determined, and eggs and sperm were collected. Sex ratio differed between reef site. Corals sampled from the northern reef had an average sex ratio of 70 males to 30 females. F. scutaria sampled in the southern reef had an average sex ratio of 12 males to 88 females. There was no significant difference in the length of individual polyps, width, egg size and sperm motility between reefs. This difference in spatial distribution and sex ratio of F. scutaria in two different reefs raises questions about the drivers of sex change and reproduction success. The study will be replicated in 2018 and 4 other reef sites will be sampled.

 

Summers, Natalie, Marine Biology
Biogeography of the upper bathyal of the Pacific Ocean

The deep sea is being impacted by a multitude of anthropogenic threats from fishing to mining, making a biogeographical scheme for the deep sea a crucial conservation priority. Schemes such as the Marine Ecoregions of the World have been developed for coastal and shelf areas where each unit or region is homogeneous and distinct from adjacent regions. Because of the lack of data on organism distribution in the deep sea, biogeographical units based on temperature, salinity, dissolved oxygen and particulate organic matter flux as oceanographic proxies were used for the lower Bathyal (800 to 3500). The addition of nitrate, phosphate and silicate data were imported into ArcGIS to create 37 3D global Ecological Units (EMUs). The aim of this study is to test proposed biogeographical units for the upper Bathyal (200-800m) in the Pacific Ocean with octocoral data using hierarchical cluster analysis. An initial test of the method using Marine Ecoregions and OBIS octocoral data showed promising results in the North Pacific. The West coast of North America appears to be one biogeographic unit related to North America and the Aleutians. Gaps in the West Pacific still need to be filled but some data is potentially available through museum databases that have not yet been digitized. Testing these units for the Pacific is an achievable goal with the available data and is an important step in determining if oceanographic variables can be used as proxies to define biogeographical provinces of the deep sea.

 

Tavares, Kammie, Geology and Geophysics
Island wide projections for potential shoreline armoring as sea level rises on Oʻahu, Hawai’i

In Hawai’i, protecting beach resources helps to preserve a high quality of life for residents, is critical to our tourism-based economy, and preserves an important coastal environment that is crucial for a number of endangered endemic and indigenous species. However, narrowing and loss due to shoreline armoring continues to threaten Hawaiian beaches. Additionally, sea level rise accelerates erosion and may also accelerate the hardening of shorelines throughout the state. Thus, modeling future beach vulnerability to armoring provides important data for developing resource management plans. We model future erosion for 0, 0.15, 0.3, 0.6, and 0.92 meters of sea level rise for the entire island of Oʻahu. Results show near-term sea level rise of 0.15 to 0.3 m triggering a cascade of seawall applications, risking sensitive beach resources. We conclude that current and near-term sea level rise, not future sea level rise, poses the greatest threat to critical habitat and therefore the greatest priority for management planning exists now.

 

Thesken, James, Mechanical Engineering
Genetic Algorithm Framework for Optimized Navigation of Collaborative Autonomous Vehicles

Autonomous vehicles are a topic of substantial interest in modern engineering, aiming to boost safety, convenience, and efficiency of infrastructure in society. The absence of human interaction within an autonomous ecosystem is necessary to be considered truly autonomous. This offers challenges for autonomous vehicle systems (AVS) in which collaborative efforts are required to achieve a task, such as in unknown environments and hazardous situations. Given the success of studies following the communication between unmanned aerial vehicles (UAV) and unmanned ground vehicles (UGV), an opportunity is present for the optimization in the creation of navigational paths in real-time. In this study we hypothesize the optimization of collaborative waypoint-navigation can be achieved via genetic algorithms, provided by real-time aerial detection of obstacles and possible paths from UAV to UGV.

 

Timmers, Molly, JIMAR/HIMB
Cryptofauna coral reef diversity across spatial and environmental gradients in the tropical Pacific

Present-day patterns of diversity across tropical Pacific coral reefs have been primarily determined from coral and fish, highly visible reef-dwelling taxa that represent only 1% of the total metazoan diversity. The remaining 99% of the diversity is comprised of a community of organisms known as the cryptofauna. The cryptofauna resides within the three-dimensional reef framework and is challenging to examine across spatial and environmental gradients in part due to the difficulty in extracting them from the reef matrix. Standardized 3-dimensional collection devices, known as Autonomous Reef Monitoring Structures (ARMS), were deployed around 22 islands across 5 regions of the tropical Pacific. Recovered units were quantitatively processed to examine motile marine invertebrate cryptofauna communities greater than 2 mm. We examine to what extent environmental factors, such as nutrients, temperature and coral cover, and geographical location explain variations in diversity. Understanding how communities and organisms vary over their present range of environmental conditions is critical if we wish to understand how coral reef communities may respond to increasing anthropogenic and global impacts.

 

Tucker, Sarah, Marine Biology
Gene marker development to examine population dynamics of a globally distributed marine bacteria

Using DNA sequence data to examine diversity at the level of populations or species is now a standard approach in phylogeographic and phylogenetic studies of marine organisms. For marine microorganisms, the SSU rRNA gene has typically been used as the gold standard to determine genetic variation among genera and sometimes species. However, this popular marker is too conserved to differentiate many species as well as population dynamics. SAR11, a globally distributed and highly abundant clade of Alphaproteobacteria, is extremely genetically diverse with significant SSU rRNA gene sequence dissimilarity among 5 major groups (equivalent to bacterial Families). In this study we develop a gene maker for the pet B (cytochrome b6) gene that codes a functional protein product and evolves more quickly than the SSU rRNA gene. By adapting this gene marker to a MiSeq platform, we will gain a unique view of the population dynamics of SAR11 across environmental gradients. The tool will also be utilized to more efficiently screen isolated cultures of SAR11 and identify strains that have genetic variation for which there exist no current genomic data.

 

Valdez, Angelica, Biology
Spawning of ‘opihi by pheromone induction using a novel synthetic GnRH peptide

To develop a novel spawning method for ‘opihi (Cellana spp.), a ʻopihi gonadotropin- releasing-hormone (oGnRH) peptide was synthesized (pGlu-H-Y-H-F-S-N-G-W-K-S-NH2) and tested for its bioactivity in side-by-side bioassays. In Bioassay 1, n=36 ʻopihi (8.22 ± 2.51 g) were administered with PBS (control), salmon GnRH or oGnRH via a two-step intramuscular injection at 250 and 500 ng g-1 body weight, BW. In Bioassay 2, n=35 ʻopihi (8.75 ± 2.75 g) were exposed to various concentrations (0, 0.05, 0.25, and 0.50 mg L-1) of sGnRHa or oGnRH in seawater. We hypothesized that the oGnRH peptide is a) bioactive, and b) can induce spawning as a pheromone.

ʻOpihi were observed to spawn from 3:45am to 7:05am in both bioassays. Our oGnRH peptide treatments resulted in the release of egg and sperm as confirmed by microscopy and by fertilization. A two-fold reduction in percent mortality was also observed between pheromone and intramuscular-injection bioassays.

These results suggest that oGnRH plays a role in reproduction of ‘opihi. Administration of oGnRH by pheromone also effectively spawned both sexes while reducing stress on valuable broodstock. Future investigations will evaluate the dose-response relationship and relative potency. These findings are crucial in moving forward an ‘opihi aquaculture industry in Hawai’i.

This material is based upon work supported by the Center for Tropical and Subtropical Agriculture through a grant from the National Institute of Food and Agriculture of the U.S. Department of Agriculture under Award No. 2014-38500-22241. Additional funding was also granted by UROP and The Hawaiian Malacological Society.

 

Veazey, Lindsay, Biology
Present-day distribution and potential spread of native invasive green alga Avrainvillea amadelpha

Algal assemblages are critical components of marine ecosystems; they act as primary producers, nutrient cyclers, and substrate providers. Coral reef ecosystems can be disrupted by stressors such as storm events, effluent inundation, sudden temperature shifts, and non-native invaders. Avrainvillea sp., also known as leather mudweed, was first recorded in the main Hawaiian Islands on the west shore of O‘ahu and has continued to be of concern due to its extreme competitiveness with native species. It has spread rapidly across the island of Oʻahu, decreasing the biodiversity of the benthos from shorelines to ~90 m depth. We employed a boosted regression tree (BRT) modeling framework using past and current distribution data to create maps identifying highly vulnerable regions prone to Avrainvillea sp. invasion. Our models indicate that relatively flat, moderately warm coastal regions exposed to minimal bottom currents are particularly susceptible to Avrainvillea sp. colonization, especially in areas adjacent to some coastal development and shipping traffic. We identified Mokuleʻia, eastern Oʻahu (southward from Kahuku through Waimānalo), and much of the Honolulu metro area (eastward from ʻEwa through Maunalua Bay) as leather mudweed hotspots of particular note for resource managers and conservationists.

 

Wallstrom, Michael, Biology
Non-native Species as alternative ecological engineers in habitat restoration: The case of Gracilaria salicornia

The continued degradation to marine ecosystems is of concern in coastal ecology restoration, as most of society depends on these ecosystems.  Restoration efforts typically are focused toward re-establishing native populations and communities; however, the longevity of restoration efforts may fail due to a continued or worsening biotic and abiotic environmental state that is unsuitable for the native species to survive. There are a rising number of studies that have shown positive impacts by non-native ecological engineers in marine coastal restoration projects. A common non-native ecological engineer in Hawaiʻi is Gracilaria salicornia. Efforts and studies have focused on the negative impacts of this species here in Hawaiʻi; however, G. salicornia has been recently used in restoration efforts with positive results on the mainland, where native ecological engineers are no longer able to thrive. The aim of the current study is to assess the possible positive impacts G. salicornia may have on the coastal ecosystem through quantifying biodiversity in sites with and without G. salicornia.

 

Wehr, Nathaniel, Natural Resources & Environmental Management
Soil microbial community response to the removal of nonnative feral pigs (Sus scrofa) from Hawaiian tropical montane wet forests

Nonnative feral pigs (Sus scrofa) are recognized throughout the Pacific Island Region as ecosystem engineers that modify habitats and alter ecosystem processes including soil physical and chemical properties. This study addresses changes in the soil microbial community following the removal of feral pigs from native Hawaiian tropical montane wet forests. This study utilizes five paired sites consisting of plots both inside (feral pigs removed) and outside (feral pigs present) management units spanning a ~25 year chronosequence of time since removal in Hawai‘i Volcanoes National Park and the adjacent Pu‘u Maka‘ala Natural Area Reserve. Soil samples were collected from the soil-litter interface at 2 m intervals in cardinal directions at each site. Microbial eDNA was extracted from soil samples using MP Biomedical’s FastDNA SPIN Kit for Soil. DNA will be sequenced using both Illumina and Nanopore sequencing techniques, and categorized to taxa. We hypothesize that soil microbial community biodiversity will decrease corresponding to decreases in the presence of fecal indicator bacteria and viruses following feral pig removal. If true, these results will indicate feral pigs as likely distributors of soil microorganisms throughout their habitats, which will provide land managers with important information needed to adequately monitor potential disease transmission by nonnative ungulates.

 

Welch, Eric, Global Environmental Science - SOEST
Soil microbial community response to the removal of nonnative feral pigs (Sus scrofa) from Hawaiian tropical montane wet forests

Pesticide use is a growing concern in society.  Pesticides in natural waters can be toxic not only to terrestrial and aquatic biota, but also to human populations along waterways.  Their presence is often studied in surface waters since streams and sediments are considered their primary pathways.  Groundwater pathways, however, have not been as thoroughly investigated since pesticides are not commonly considered mobile enough for subsurface dispersal.  Pesticide transport through aquifers may take several decades before eventually reaching drinking water sources or the marine environment. 

Groundwater and surface water interactions were investigated as a pathway of pesticide migration on the island Tutuila of American Samoa during a study in August 2016 to examine contaminant transport paths.  Samples were collected across the island to analyze for selected pesticides (glyphosate, imidacloprid, azoxystrobin, DDT/DDE).  An additional focus-study was conducted in the Faga`alu watershed, where field data was integrated into a groundwater model to reconstruct flow paths and pesticide dispersal.  In combination with land-use maps, these models were used to identify potential pesticide sources and their contaminant contributions. 

Although all measured pesticide concentrations on Tutuila were well below EPA regulated limits, they were transported at much higher fluxes via groundwater pathways (~70%) than through surface runoff (~30%).  This proves the significance of subsurface flow in regards to contaminant transport.  Our modeled submarine groundwater discharge (SGD) and riverine-groundwater-contribution thus indicate that groundwater comprises a significant percentage of the watershed’s pesticide flux, and cannot be overlooked. 

 

Wishingrad, Van, Biology
Identifying morphologically variable garter snakes (Thamnophis spp.) by genetic sequencing

Garter snakes (genus Thamnophis) are notoriously difficult to identify due to high levels of variation in coloration and meristic (scale) traits. Field herpetologists therefore often rely heavily on geographic location to identify species, but this practice can lead to misidentifications, and is less useful when range changes occur. Furthermore, while Thamnophis includes some of the most common and abundant snakes in North America, phylogenetic relationships among the ~31 recognized species are not well understood. However, generally well-resolved mitochondrial (mtDNA) gene trees means that genetic sequencing of mtDNA can be a powerful tool in identifying unknown species. Here, I sequenced three mtDNA genes (ND2, ND4, and cytb) to infer the identity of a garter snake that could not be identified to species-level based on morphology alone. Examination of the specimen suggested it was a northwestern garter snake (T. ordinoides), and could therefore represent evidence of an impressive >150 mile range expansion. All three gene trees place the unknown Thamnophis individual within the T. atratus clade, despite expected patterns of gene-tree discordance and individual gene-tree topology variation. These results strongly suggest the unknown garter snake is an aquatic garter snake (T. atratus). A pervasive issue in garter snake phylogenetics is the paucity of genetic data currently available. Investments in genetic sample collection, genetic sequencing, and phylogenetic analysis should therefore be made, as these would contribute greatly to our understanding of North American biodiversity in general, and a major faunal lineage in an area of high herpetological endemism and diversity in particular.

 

Worsham, McLean, Zoology
Epigenetic regulation in adaptive traits of the Mexican cavefish

Epigenetic mechanisms modify gene expressions without changing genomic nucleotide composition in response to the given environment. This mechanism may contribute to rapid adaptation within a single generation in response to environmental change; therefore, epigenetics has been proposed as one of the driver of organismal evolution (Skinner 2015). However, it is largely unknown how this mechanism actually plays a role in evolution; for example, whether epigenetic modification on a particular gene(s) promotes adaptive shift in traits. The present research strives to determine the effects of epigenetics modification in trait evolution. Mexican cave tetra is an established model system for evolutionary research, composed of ancestral eyed surface-form and derived eyeless cave-forms. Cave-forms have evolved multiple traits—some of them show proven advantages in cave environments with parental genetic effects, potentially under epigenetic regulation: maternal genetic effect in smaller eye sizes, and paternal genetic effect in the increased number of mechanosensory lateral line units and the higher level of vibration attraction behavior (VAB; a cave adaptive behavior). Here we treated inhibitors for DNA methyltransferase and histone deacetylase, which are major epigenetic regulators. This treatment was performed for 1-2 weeks from (1) embryonic stage for eye size development, and (2) young adult stage (~6 month old) where cavefish express strong VAB. Our preliminary result showed that eye-size varied more (S.D. from 0.027 to 0.041) in cavefish, however, no detectable effect in VAB. We are currently repeating these experiments, including the tests in different developmental stages, and are performing technical development for bisulfate sequencing.

 

Yadav, Shreya, Marine Biology
Teresa Alcoverro, Nature Conservation Foundation, India
Rohan Arthur, Nature Conservation Foundation, India
Coral reefs respond to repeated ENSO events with increasing resistance but reduced recovery capacities in the Lakshadweep archipelago

The resilience of reefs to repeated, increasingly frequent thermal disturbance is a dynamic balance between resistance and recovery pathways. The Lakshadweep archipelago in the central Indian Ocean has experienced three El Niño Southern Oscillation (ENSO) events in 1998, 2010 and 2016. Using a multi-decadal monitoring of 6 shallow reefs, we estimated reef resistance and recovery after each of these bleaching events. Coral resistance increased with successive bleaching event; coral mortality was 87%, 44% and 31% after the 1998, 2010 and 2016 ENSOs even as the severity of each event increased. In contrast, benthic recovery after the 2010 disturbance was more protracted than post-1998, with up to 4-fold decrease in recovery rates between the two time periods. Overall coral cover declined from 51.6% in 1998 to 11% in 2017. We examined the demographic and compositional mechanisms underlying the two recovery trajectories by monitoring coral recruitment, juvenile, and young adult composition for five years after 1998 and 2010. While coral juvenile densities were comparable after each of these disturbances, densities of fast-growing Acroporids reduced from >1/ m2 post-1998 to 0.09/ m2 post-2010. In the second recovery period reefs also appeared to have shifted to a stress-tolerant, bleaching resistant coral composition. While this shift to a more thermally resistant assemblage signals a system adapting to recurrent thermal anomalies, the dramatic reduction in fast-growing, habitat-forming corals like Acropora, and, to a lesser extent, Pocillopora, is driving a major decline in recovery rates with time. This shift also signals a transition to structurally simpler reefs with potentially reduced function. Given the frequency of current warming events, the increased reef resistance over the last two decades is likely not sufficient to also ensure gains in coral cover in Lakshadweep's reefs.

 

Young, Emily, Oceanography
Wood-eating clams, bone-eating worms and all that accompany them: Community structure and ecosystem function of deep-sea organic-rich habitats in the NE Pacific.

Organic-rich habitat islands such as whale-bones and wood-falls may contribute fundamentally to biodiversity, evolutionary novelty, connectivity and ecosystem function within the deep sea. However, our current understanding of organic-fall community structure and ecosystem function is largely qualitative due to constraints associated to adequately sampling such patchy and ephemeral deep-sea habitats. Here we discuss a comparative, experimental approach to quantitatively investigate interactions between biodiversity, connectivity and ecosystem-function of whale-bone and wood-fall habitats, over differing bathymetric ranges and geographical locations. We are specifically interested in elucidating the role of key ecosystem engineers in promoting species diversity and substrate decomposition in deep-sea organic fall habitats. Four identical benthic landers holding replicate wood, bone and inorganic hard substrates were deployed for 15 months to depths of 1500 and 3000 m, spaced ~400 km along the Washington-Oregon margin. This approach allowed for the collection of taxonomically and functionally diverse macrofaunal communities, key ecosystem engineering (decomposer) taxa, and estimations of substrate decomposition rates. Multivariate analyses revealed that epifaunal community composition and structure varied initially by depth, followed by within-depth location and substrate type. The abundance of wood-boring bivalves (genus Xylophaga) was greatest in wood substrates deployed to 1500 m, which resulted in a loss of 89% (±3.9%) of the wood by dry weight and facilitated the colonisation of an abundant and diverse wood-fall community, highlighting the ecosystem engineering role of these decomposer taxa.

 

Zhang, Rui-Yang, MBBE
Conopeptie, MIIIB, provides novel insights into Methionine directed peptide structural stabilization

The goal of this project is to determine what unique peptide backbone properties are associated with the novel inter-cysteine loop and N-terminal methionine containing conopeptide MIIIB and if these properties can be eventually applied to the development of drug, pesticide, or selective molecular probe candidates for specific ion channels. One of the prevalent strategies of peptide therapeutic development is the application of peptide backbones as scaffolds in rational drug design, which maintain the bioactive three-dimensional structure along with specific residue modifications within the pharmacophore to fulfill pharmacological purposes. Given the characteristics that small-sized conotoxins contain similar secondary structural elements to large-sized proteins, it is possible that there are more significant structural stabilizing factors other than disulfide connectivity dominating the folding of conotoxins. In this study, a unique Conus peptide is presented which preliminary research has indicated the manipulation of the N-terminal methionine influences the formation and bioactivity of the bioactive isoform. We believe this unusual N-terminal methionine could play an additionally important role for structural stabilization and folding of conotoxins, or contribute to the stabilization of rationally designed peptides in the future.   

Categories
Last Modified: 
04/25/2018 at 10:13am