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COAST Award Program
Joint Meeting of Ichthyologists and Herpetologists/32nd Annual Meeting of the American Elasmobranch Society, New Orelans, LA
Feeling the heat, seasonally acclimated metabolic Q10 of the California horn shark, Heterodontus francisci
With global sea temperature rise, it is unclear how many marine ectothermic organisms will react, particularly elasmobranchs. A better understanding of their metabolic Q10, temperature sensitivity, is needed in order to make realistic predictions as to how some populations will react over time. Oxygen consumption was used as a proxy to measure acclimated metabolic rates of the horn shark, Heterodontus francisci, at winter and summer temperatures (16C and 20C, respectively) typically experienced in a given year and to measure metabolic Q10. Sharks were kept in a large holding tank at one of the desired temperatures for two weeks prior to the trial to allow for physiological acclimation. Trial duration varied among individuals and temperature, trials took up to 12 hours with re-saturation of oxygen occurring when levels reached 80% of starting saturation. Sharks tested to date have ranged in size (37-45cm TL) and weight (0.41-0.679 kg) (n = 8). The resting, pre-prandial metabolic rates of the horn shark at 16C and 20C were 32.6 +/- 9.5 mg O2 kg-1 hr-1 and 44.4 +/- 8.8 mg O2 kg-1 hr-1, respectively. Of the eight horn sharks that we have tested, we estimate a metabolic Q10 of 2.31. These data provide a baseline for understanding the current physiological state of these organisms relative to present sea conditions, but can be modeled to help predict and manage behavioral responses associated with increased sea temperature.
16th International Symposium on Microbial Ecology, Montreal, Canada
Variation of carbon use of microbial communities in different microhabitats
Microbial communities play an important role in the health of ecosystems and changing environmental microbial communities results in altered ecosystem function. The type and abundance of carbon sources affects the demographic rates of the microbes. Culture experiments determined that microbes have differing abilities to breakdown carbon sources and our experiment aims to investigate the response of environmental microbial communities to various carbon compounds. We hypothesize that microhabitats will drive carbon usage, rather than geographic location. We will evaluate our hypothesis by testing samples from two tide pool locations, Ocean Beach and Mission Beach, on three carbon sources; malic acid, cellobiose, and erythritol. From each location we will collect samples from three microhabitats, water column, hermit crabs, and algae. To compare the differences in nutritional abilities based on tide pool location and microhabitat (water, hermit crab or algae), we will grow the microbes on the three carbon sources and identify the proportion of microbes able that grow. The proportional differences across the plate types will be tested using a 2 factorial ANOVA, with microhabitat nested in location. We predict that the samples collected from each microhabitat will have different utilization of the carbon sources and that the sites that we sample from will not affect the usage of carbon sources by these three microhabitats. This data will show that different microhabitats have specific microbial communities, and that each of these microbial communities requires different nutrients. Our findings will describe the nutrient usages of microbial communities in differing environmental conditions and microhabitats.
Western Society of Naturalists Annual Meeting 2017, Monterey CA
The keystone predator Pisaster ochraceus has strong effects on the vertical distribution of the foundation species Mytilus californianus, but the effect of other predators on mussel distribution has rarely been studied in the absence of stars. With the onset of seastar wasting disease (SSWD) and depletion of west coast star populations, investigating how vertical distributions of mussels change when Pisaster is absent will be important for understanding future rocky shore community structure. We examined the effects of crab predation on Mytilus in the absence of Pisaster predation by re-locating stars and transplanting mussels to different tidal heights on a rocky shore in Northern California. When transplanted at low tidal elevations, uncaged mussels showed increased mortality compared to caged mussels at low elevations, and caged and uncaged transplanted mussels at high elevations. Crab attacks on wax snail replicas confirmed mortality on mussels at low elevations were due to crab predation. Both caged and uncaged mussels transplanted to high tidal elevations also experienced mortality, but this was due to disturbance from strong wave forces. Our results suggest that on rocky shores where Pisaster are absent or have been depleted by SSWD, lower limits of Mytilus distributions may be maintained by predatory crabs.
The non-lethal effects of predators on predatory whelk, Nucella lamellosa, shell morphology
Predators not only consume prey , they also non-consumptively affect prey by inducing plastic physical defenses. Such predator induced phenotypic plasticity has been extensively studied in laboratory settings, but its ecological significance in nature is still undetermined. In mesocosms, predatory whelks, Nucella lamellosa, alter their shell shape in the presence of crabs (Cancer productus) and seastars (Pisaster ochraceus). I examined whether these results are reflected in nature by surveying N. lamellosa from 5 rocky intertidal sites in Northern California. I quantified geometric metrics of N. lamellosa shell shape and tested their relationship against three environmental variables: water temperature, wave force, and the densities of crabs and seastars. Responses to predator densities in the field were similar to those reported in mesocosms. Whelks from sites with higher crab density had thicker, wider shells that combat crushing; whelks from sites with higher sea star density had elongate, high-spired shells that combat shell entry. Further research is needed to rule out locally adapted genetic variation between sites; however, N. lamellosa’s plastic response to non-consumptive predator effects in the field parallels the difference in shell shape determined in mesocosm experiments, implying that predator-induced phenotypic plasticity is possibly driving patterns of morphological variation in nature.
Avian use of mudflat habitat prior to living shorelines restoration
Living Shorelines restoration uses the infrastructure that some organisms (e.g., oysters, eelgrass) create to reduce coastal erosion while simultaneously promoting ecological community health. Birds may benefit from living shorelines because restored habitat may increase the amount and diversity of prey species. Bird density and richness increased in response to creation of living shorelines in San Francisco Bay, but this effect has not been evaluated in southern California estuaries. We studied avian use of mudflats at four sites prior to eelgrass and oyster restoration in Newport Bay, CA by conducting scan and focal samples between January-June 2016 at -0.5ft MLLW and lower. Each site consisted of a 130m long x 12m wide mudflat swath, divided into four 20m long treatment plots (control, oyster, eelgrass, oyster-eelgrass) with 10m buffer zones. We found no significant differences in bird density and richness within and among sites. Post-restoration surveys through spring 2017 will examine bird response to eelgrass restoration (completed July 2016) and oyster restoration (planned March, 2017). We predict the largest increase in bird density and richness in treatments that contain both restored eelgrass and oysters, which would support simultaneous oyster- eelgrass restoration as an approach in promoting healthy communities.
Commercial topical sunscreens are detrimental to development of the purple sea urchin, Stronglyocentrotus purpuratus
Commercial sunscreens provide humans protection against ultraviolet radiation. Nevertheless, these sunscreens can dissolve off of human skin during swimming and snorkeling activities and may have detrimental effects of marine organisms. Some of the active ingredients in sunscreens including oxybenzone and titanium dioxide cause the production of hydrogen peroxide in the water column, which causes oxidative stress to marine organisms. One sunscreen company is trying to create less harmful products and asked us to determine whether their zinc oxide-based sunscreen may be safe for marine organisms. We tested effects of this sunscreen on embryos of the purple sea urchin, Strongylocentrotus purpuratus, which are commonly used for toxicology studies. This is also an important organism to marine ecosystems. We hypothesized that any commercial sunscreen may be harmful to embryos of marine organisms and we predict that higher concentrations of sunscreens will be more detrimental. We examined how various concentrations of sunscreen in seawater affect multiple stages of sea urchin development, including the time to first cleavage and the percent normal developmental to the blastula, gastrula, prism and pluteus stages. Exposure of embryos to sunscreen caused developmental abnormalities in both early cleavage and later embryonic development in a concentration-dependent fashion (ANOVA P<0.05).
Society for Integrative and Comparative Biology Annual Meeting 2017, New Orleans, LA
Temperature influences on reproductive endocrinology of the estuarine sheepshead minnow Cyprinodon variegatus
Temperature plays an important role in regulating reproduction in many temperate fishes. The estuarine sheepshead minnow Cyprinodon variegatus serves as a useful model for studying temperature effects on reproduction because it exhibits one of the widest thermal tolerance ranges of any fish. Here, we examined the effects of thermal environment on reproductive function in sheepshead minnows by comparing gonadosomatic index (GSI) and relative transcript levels for genes associated with gonadal steroidogenesis in sexually-mature minnows maintained at 25°C or 35°C for 14-15 days. Both females and males maintained at 35°C exhibited a smaller GSI than fish at 25°C. In addition, females at 35°C showed lower relative levels of mRNA transcripts encoding follicle-stimulating hormone receptor (fshr) and luteinizing hormone receptor (lhr) as well as cholesterol side chain cleavage enzyme (p450scc) and steroid acute regulatory protein (star). Females kept at 35°C also exhibited lower levels of mRNAs encoding two steroidogenic enzymes: ovarian aromatase (cyp19a1a) and 3b-hydroxysteroid dehydrogenase (3bhsd). Similar to females, males kept at 35°C exhibited lower relative levels of lhr mRNAs in the testis than males kept at 25°C. However, no difference was observed in fshr mRNA levels. Males at 35°C also had lower testicular levels of mRNAs encoding p450scc, but there was no difference in star mRNA levels. There was no effect of temperature on mRNA abundance for cyp19a1a or 3bhsd in the testis. Taken together our results imply that despite the phenomenal thermal range exhibited by C. variegatus, individuals experience decreased reproductive performance at 35°C even though this temperature is well within the species' thermal tolerance range.
Under pressure: Electronic instrumentation methods affect fur seal pelt function during simulated dives
The tracking of marine mammals with electronic devices enables researchers to gain a better understanding of their movements and at sea behavior. In pinnipeds (seals and sea lions), electronic instruments are typically glued to the animal’s fur, either directly to the pelage or on a neoprene patch. When instruments are recovered for data collection they are retrieved either by cutting the fur or by cutting through the neoprene patch and leaving a layer of neoprene attached to the animal. The impact of these modifications to the animal’s pelage is presumed to be minimal, but this has not been explicitly investigated. This study examined the effects of instrument attachment and removal on the pelts of northern fur seals. Northern fur seals rely primarily on their fur for insulation in water and are thus ideal for determining the impacts of instrumentation on pelage function. To assess the extent to which water is able to penetrate the air layer of fur seal pelts during diving, we measured the volume of air released under hydrostatic pressure. Dives to 120m were simulated in a hyperbaric chamber for (a) unmodified pelts, (b) pelts with the top layer of fur cut, and (c) pelts with a layer of neoprene attached. We also measured the thermal conductivity of unmodified and modified pelts for both instrumentation methods. Cutting the fur during tag removal allowed water to penetrate the fur under pressure and reduced the thermal function of the pelt in water. In contrast, a neoprene patch better maintained the air layer and the insulation. This is the first study to measure the thermal consequences of instrumentation in fur seals and the results suggest that the use of neoprene in instrument attachment may minimize those consequences
Characterizing the Biodiversity of Botryllids in the Philippines Through CO1 Barcoding
Botryllids are marine invertebrates renowned for their advanced allorecognition and regenerative capabilities. These traits show intriguing patterns across clades and species. However, much of what is understood about the reproductive behavior and distribution in benthic and fouling communities is based on what is known from invasive botryllids. Here, we take advantage of a substantial natural assemblage of ascidians from the Verde Island Passage of the Philippines, coined the center of the center of marine biodiversity in the Coral Triangle. Our findings show a large diversity of botryllids in an area that is roughly 100 km2. Our data show 11 novel mitochondrial cytochrome oxidase 1 (CO1) haplotypes in just 14 samples, that includes a remarkable discovery of 4 new clades as well. Biodiversity observed to this extent in an area this size is unlike any currently known marine habitat. Furthermore, of the currently characterized globally invasive species of botryllids, none were detected to date in this prodigiously biodiverse ecosystem. This project is the primary measure towards linking molecular data with historic species descriptions based on morphological features and a preliminary component of characterizing botryllid biodiversity.
American Society for Engineering Education, Columbus, OH
Method for a Low Cost Hydrokinetic Test Platform: an Open Source Water Flume
Many undergraduate universities and educational institutions do not possess the capabilities to perform hydrodynamic testing, either for laboratory purposes or for design testing. The goal of this paper is to outline and describe a water flume system designed to allow universities and educational institutions to perform hydrodynamic testing for a relatively low cost, and in an open source platform. Driven by the need for a simple and convenient way to test a water turbine, a low cost closed-loop variable velocity water flume was designed, constructed, and tested that allows for simple hydrodynamic testing. The water flume differs from a water tunnel in that it has an atmospheric free surface instead of being entirely enclosed. Additionally, the design of this water flume incorporates a removable converging-diverging insert that allows for further variation flow velocities within the test section. This design allows for the study and quantitative measurement of: immersed body drag, ship hull design testing, tidal energy platform testing, and many other hydrodynamic tests/labs. The design is a self-contained system with a 74”x48”x48” overall footprint, incorporating a water holding tank for when the system is not in use, reducing the environmental impact of draining and filling the system. The system utilizes a commonly available single-stage centrifugal pump powered by a conventional 110V power receptacle. Flow is controlled by the previously discussed insert and with a recirculation valve. The total cost for this project was approximately $3500, required 3 months of part-time work to construct, and allowing for a maximum flow velocity of 0.70 ft/s within a 6”x12”x12” test section. This paper presents: the methodology behind this design, the testing process, a step-by-step construction process including bill of materials, challenges encountered and overcome during the design process, and other pertinent information.
American Chemical Society National Meeting, San Francisco, CA
Determination of total copper concentration and copper speciation in Humboldt Bay, California through use of competitive ligand exchange-adsorptive cathodic stripping voltammetry
Copper (II) is considered to be the most bio-available, as well as toxic, form of copper in aquatic environments. Mollusks are especially prone to copper toxicity and are commonly used in copper toxicity tests for estuarine and marine systems. This work reports the first copper speciation measurements in Humboldt Bay, where over 90% of California's oysters are farmed for human consumption. The study used an established competitive ligand exchange-adsorptive cathodic stripping voltammetry (CLE-ACSV) method. Salicylaldoxime (SA) was used as the competitive ligand and samples were buffered to pH = 7.8 with EPPS. A hanging mercury drop electrode (HDME) was used in the subsequent experiments with a deposition potential of 0.15 V for 60 seconds, and then scanned in differential pulse mode from 0.15 V to 0.60 V at 20 mV/s. Copper speciation and total dissolved copper concentrations were determined in water samples using the described method, and the results show that essentially all of the copper in Humboldt Bay was bound to strong-binding ligands and was not bioavailable. Total dissolved concentrations of copper were below the EPA water quality criterion for saltwater ecosystems (samples ranged from or 0.12-1.39 ppb, or 2-22 nM, with an EPA mandated limit of 2.8 ppb). Electrochemical measurements of the speciation agreed with copper water effect ratio (WER) results from Humboldt Bay waters. The study concludes that there is low risk of copper toxicity to occur in Humboldt Bay.
American Chemical Society National Meeting, San Francisco, CA
Comparison of the persistence of caffeine in constructed wetlands versus convention wastewater treatment systems
Caffeine was used as an emerging pollutant indicator, to compare the persistence of caffeine in a constructed wetland system designed to treat wastewater, in Arcata California, versus three local conventional wastewater treatment systems of different design. Caffeine was isolated from the wastewater with solid phase extraction (SPE) techniques and measured using high performance liquid chromatography (HPLC) with absorbance detection. In the Arcata Marsh, caffeine concentrations ranged from 36.5 - 113 ppb in the primary influent and effluent. As for the conventional treatment facilities, caffeine concentrations in primary influent and effluent varied from 57.2 - 165 ppb. Caffeine persisted in secondary effluent with levels ranging from 2.23 - 6.39 ppb. However, after the use of UV or chlorine disinfection, levels of caffeine could no longer be detected. The study showed that the biologically-rich environment in constructed wetlands readily degraded caffeine from the wastewater compared to treatment systems at conventional wastewater facilities
Geological Society of American Annual Meeting: Cordilleran Section, Honolulu, Hawaii
Late holocene climate variability from St. Croix, USVI reef corals
We present a multi-century climate record using the skeletal geochemistry of Siderastrea siderea and Orbicella faveolata corals collected near Salt River Bay, St. Croix, USVI. Samples ranging in age from modern to approximately 2100 years old were collected, slabbed, and milled with each coral representing approximately 25 to 40 years of growth. Skeletal δ18O values correlate strongly with sea surface temperature (SST) and sea surface salinity (SSS). Seasonal variations in skeletal δ18O values are controlled primarily by changes in SST and secondarily by inferred changes in water δ18O due to precipitation and runoff. Analysis of these variations in the St. Croix corals indicates either a decline in SST or an increase in SSS over the last several centuries. The remaining coral slabs were analyzed with Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) for trace element geochemistry. Unusually high ratios of Ba/Ca correspond with an influx of sediment typically associated with increased runoff from storm events. The presence of spikes in Ba/Ca may indicate that seasonal variations in skeletal δ18O values result from an increase in SSS instead of a decline in SST.
Annual Meeting for the Society of Wetland Scientists, San Juan, Puerto Rico
Relation of Food Source Availability at Huntington State Beach to the California Least Terns (Sternula antillarum browni) Diet
The California Least Tern (Sternula antillarum browni) is a federally endangered bird due to habitat loss and predation. Food availability, often reduced as habitats are lost or degraded, impacts nesting success and fledgling survival. Our study focused on the Huntington State Beach tern preserve and how food availability affects the diet of California Least Terns. The Huntington State Beach tern preserve has access to both the Pacific Ocean (marine habitat) and the Santa Ana River (tidal riverine habitat). Seines were conducted at both habitats during the mating, chick, and fledgling stages of the California Least Tern mating season. We determined that fish abundance, species richness, and community composition did not differ between habitats but topsmelt was the most abundant food source in both locations. Additionally, we found that topsmelt were significantly smaller during the chick and fledgling stages than during the mating stage. Further, using behavioral observations, we determined that more foraging was completed in the marine habitat rather than the tidal riverine habitat. Preliminary guano analysis data also suggest that Atherinopsidae is the predominant diet source. This study shed light on food availability in differing habitats and locational foraging preference as it relates to the overall health and survival of the endangered California Least Tern at this colony.
Impacts of Invasive Tamarix and its Removal on the Invertebrate Community in Tijuana Estuary
Tamarix spp., introduced from Eurasia and Africa to North America in the 1800s, is one of the most problematic invasive species in the United States. Its impacts are well-known in riparian and desert ecosystems. Recently Tamarix has been observed to invade salt water systems. Our study was conducted in Tijuana Estuary, a salt marsh where Tamarix colonized and was subsequently the target of an eradication program. Pre-treatment infaunal invertebrate samples were collected in a paired design under Tamarix and non-Tamarix canopies. Infaunal invertebrate communities differed between non-Tamarix and Tamarix areas although the differences varied by season and year. Two years and ten years after treatment, we collected paired invertebrate samples at the same sites, now non-Tamarix and Tamarix treatment sites. No significant differences in the invertebrate abundance, species richness or community composition exists between Tamarix-removal and non-Tamarix canopies at the two year point. Ten year post-treatment shows that approximately 50% of the treated Tamarix have re-sprouted in the areas that experience higher tidal inundation with a lower percentage resprouting in drier areas. We see similar invertebrate communities between Tamarix and non-Tamarix areas throughout the different marsh zones. Due to mouth closure and the resultant low salinity conditions at the estuary this past spring, suitable conditions for resprouting of Tamarix was a concern. A recent survey revealed no new germination potentially related to lack of large-scale disturbance at the same time as the low salinity event. Understanding both the conditions for germination as well as success of treatment in removing Tamarix plants and in restoring invertebrate communities is important to effective management of this salt march invader.
Observation of pollution in skies above seawater and costal areas using dynamic self-guided UAV
Comparative study of the chemotactic capacity of fresh water and marine diatom species towards silicic acid nutrient sources
Are pinnipeds breeding on the Channel Islands in danger of contracting coccidioidomycosis?
Dynamic route planning UAV project
Coastal mapping with lasers and drones
Autonomous floating detector for monitoring illegal fishing activities in coastal waters
The effects of incubation temperature on salmonid egg and alevin survival and growth
Determining the relationship between biological iron oxidation and mercury mobility in an estuarine salt marsh
Aquaculture threatened by global climate change: Microbiome responses of purple-hinge rock scallop (Crassadoma gigantea) to decreased pH and increased temperature
Evaluation of urban runoff effects on the diversity and density of marine diatoms in the littoral zone surrounding Palos Verdes Peninsula
Are sea slugs immune to chemical weapons?
Active sniffing by sea slug rhinophores is enchanced by brain neurons
The role of disturbance on San Joaquin River macroinvertebrate assemblages; Implications for Chinook Salmon survival and growth
A phylogenetic perspective on the evolution of body shape in hagfish
Adjustments of temperature – Specific growth rates for juvenile Chinook Salmon in the San Joaquin Watershed
Effects of thermal stress and population density on Vitellogenin (Vg) levels in the hemolymph of the anomuran crab Petrolisthes cinctipes.
Outcompeted or outbred? Localized extirpation of a native mussel via interspecific hybridization with a highly invasive congener.
Hydrodynamic forces on the surfgrass Phyllospadix and the role that epiphytes play in breakage
Effect of intra-individual variability in chemical composition in the kelp Egregia menziesii on the feeding preference of intertidal herbivores
Ocean acidification effects on calcified structures of California grunion larvae at hatching
Determination of the copper speciation in Humboldt Bay
The effects of caffeine in marine systems on zooxanthellae symbionts
Ocean acidification acclimation potential of coralline algae when exposed to tidally driven variation
Land-based marine integrated multi-trophic aquaculture system
Recolonization rate of purple urchins
Determination of genotype influence on sea star associated densovirus load and sea star wasting disease symptoms
How stressor influence the lytic activity in Anthopleura elegantissima
Effects of shell shape and shell thickness on Nucella lamellosa shell strength
Investigating the viability of triploidy in Haliotis rufescens utilizing caffeine
Determining temperature-performance of the aerobic enzyme, citrate synthase, as a way of predicting thermal habitat range in the three species of California echinoderms.
Relation of food source availability at Huntington State Beach to the California Least Tern (Sternula antillarum browni) diet
Assessing the dissemination potential of tachyzoite stages of Toxoplasma gondii parasites during exposure to coastal California seawater conditions: exploring a new pathway to marine mammal infections.
The effect of restoration on extreme hypersaline viruses in a solar saltern
Interspecific competition and multivariate natural selection set range limits for a coastal sea slug