The North American river otter, Lontra canadensis, population is widely distributed throughout the Northern Hemisphere, but has become increasingly rare in some areas due to anthropogenic effects. L. canadensis feeds primarily on shallow-water fish. Research has shown that L. canadensis feeds on crustaceans, insects, and birds. Feces are deposited in communal latrine sites along with scented mucilaginous material to mark territory. Foundational research was conducted between October 2012 and March 2013 in the Snohomish River Estuary to uncover the population distribution, predominant food sources, and presence of protozoa contaminants near Jetty Island at Everett, WA. Remote camera deployment recorded two individuals frequenting one of the latrine sites centrally located on Jetty Island, however, there have been no cameras deployed on North Jetty. Protozoan presence was not observed in preliminary samples. Thirty percent of collected samples are predominately fish scales and bones, while the remaining samples are crustaceans. Fifty-three percent of otoliths analyzed were Sebastes sp., which has been endangered since 2010. This research will help further understanding of the apex predator's behavior and predator-prey relationship in the estuarine system.

Marine ecosystems are vulnerable to anthropogenic influences due to increased stresses from climate change and habitat destruction. Fish farming, aquaculture, and the pollutants of antibiotics and organic matter produced by them are one influence that has been observed to affect local marine wildlife leading to increased resistance to bacterial pathogens and increased algae cover. Rocky Intertidal Zones of the Pacific Northwest are environments that are under intense thermal and desiccation stresses. The unique organisms that inhabit these areas have adapted to live under these high stress conditions. I researched the effects of fish farms and oyster farms on the health of rocky intertidal communities, by quantifying shifts in species richness and biodiversity, near the aquaculture sites. The research took place in Barkley Sound between January 26th and February 2nd in 2013 on rocky beaches near fish farms, oyster farms, and control sites away from aquaculture locations. Ecosystem health was determined by evaluating species richness, bio diversity, and presence of keystone predator, Pisaster ochraceus, using standard quadrant surveys. I collected water samples for Solid Phase Extraction and Liquid Chromatography Mass Spectrometry to determine concentrations of anthropogenic antibiotics released from fish farms. I hypothesized that the presence of antibiotics will decrease biodiversity and species richness in rocky intertidal communities. Determining what effect and how strong of an impact these influences have on the environment may help define future environmental policies and fish farming protocols.

Hypoxia is the term used in aquatic systems to describe low concentrations of dissolved oxygen (i.e. ≤ 2 mg O2¬/ml). Over the past 30 years, the intensity and duration of hypoxia has increased worldwide, with notable examples in the Gulf of Mexico, Chesapeake Bay, and Hood Canal, WA. Increased nutrient pollution from anthropogenic sources like agricultural fertilizers and raw sewage is contributing to the increased phenomenon of intense hypoxia in aquatic systems. Low dissolved oxygen is not only a major stressor to fishes, but may also be responsible for dramatic ecosystem shifts with respect to energy flows through the food chain. Zooplankton communities, an important energy source for fishes, were analyzed in Hood Canal, WA in relation to summer hypoxia. Zooplankton abundance, taxonomic composition, biomass, and length distributions were compared between areas of Hood Canal that experienced moderate versus intense hypoxia at the beginning and end of the summer hypoxia season. The goal of the project is to track differences in zooplankton composition between the two sites, with intense hypoxia relating to a shift towards smaller types of zooplankton and more gelatinous organisms relative to the site with moderate hypoxia. The size of zooplankton will potentially affect the efficiency of energy transfer between zooplankton and fishes, with larger zooplankton transferring more energy relative to smaller zooplankton. Gelatinous organisms like jellyfish, siphonophores, and ctenophores generally have lower oxygen requirements and few predators. Thus, an increase in these organisms is a ‘trophic dead end,’ shunting energy that may otherwise contribute towards fish growth. Analyzing trophic changes in Hood Canal in response to hypoxia will provide insight into major ecosystem changes occurring as a result of anthropogenic perturbations.

Exploration of the geological structure of the seafloor is dependent upon acquiring accurate bathymetric data which includes representation of not only depth, but also a characterization of the acoustic backscatter due to absorption by the seafloor. Calibration of the Multibeam Echo Sounder system (MBES) used to acquire these data while the vessel experiences movement in heave, pitch, and roll, provides for accurate and comparative data between vessels and over time. This research investigates the use of the calibration methodology available with new post-processing sonar software prior to data acquisition. A patch test was conducted off the coast of Washington in early 2013 aboard the R/V Thomas G. Thompson using the Kongsberg EM302 multibeam sonar.  The data obtained from this patch test were used as a case study.  The new post-processing software is predicted to provide a more accurate bathymetric surface representation after the calibration method is performed.  Results and recommendation from the calibration test are presented.

Nitrogen (N) is an essential element of life that organisms need to make DNA and proteins. Unlike other essential elements such as phosphorous, nitrogen takes many different forms (NH₄⁺, N₂O, NO, NO₂^-, NO₃,  N₂) which are constantly cycling in the recently revised oceanic nitrogen cycle. One group in the Archaeal domain of life, ammonium-oxidizing Archaea (AOA), has recently been discovered to be a key player in the oceanic nitrogen cycle. In this cycle, Archaea oxidize ammonium (NH₄⁺) into nitrite (NO₂^-) in a process called nitrification. We hypothesized that different abiotic factors such as copper, light, and temperature regulate the physiology and depth distribution of the AOA. To test our hypothesis, we conducted ¹⁵NH₄⁺-oxidation experiments in July 2012 aboard the R/V Clifford A. Barnes in Hood Canal, Washington. Samples of seawater were filled in bottles, spiked with ¹⁵NH₄⁺, and incubated for 10 hours. We measured the oxidation of the ¹⁵N isotope using mass spectrometry, and compared the rates for control treatments to rates for treatments amended by copper (Cu), light, and other factors. ¹⁵NH₄⁺-oxidation rates were consistently low at the surface, increased until 30-40 m, and decreased to 115 m depth. Our experiments clearly showed light inhibition of ¹⁵NH₄⁺-oxidation, but the data did not clearly determine whether sunlight-produced peroxides inhibited AOA. Copper additions in Cu-deplete regions increased nitrification, possibly because the key enzyme in ammonium oxidation (amoA) is Cu-dependent. TETA, a chelator that binds Cu, did not show any effect when added during incubations. All together our results suggest that Archaea are Cu-limited, but may store Cu in small amounts. This project is part of a larger interdisciplinary effort to understand the oceanic microbes and the impacts they have on biodiversity and greenhouse gases such as N₂O and CO₂. Future studies in 2013 will extend these experiments to the open ocean.

This project seeks to better understand climate change corollary to the migration of the Intertropical Convergence Zone (ITCZ) in the tropical Pacific from the Little Ice Age (~AD 1400-1850) to the present using hydrogen isotopes as a proxy for climate change. During this time, the ITCZ is hypothesized to have reached its most southern location, the consequences of which were evident on a global scale. However, more research is needed to further investigate this hypothesis. Specifically, this study examines hydrogen isotope ratios of the source specific lipids Taraxerol and Dinosterol from Lake Escondido, Isabela Island, Galapagos. Lipids were solvent-extracted from sections of the cores, separated through silica gel columns, and the ratio of Deuterium and Hydrogen (δD) of specific lipids was quantified using a Gas Chromatograph-Isotope Ratio Mass Spectrometer. The combined fluxes of both terrestrially and aquatically sourced δD ratios over time provide a proxy for climate change through the present. Due to the widespread effects of the ITCZ on global hydrology, understanding its movement, and what triggers migration, can provide insight into future climate scenarios.

With sea level projected to rise by as much as 2 meters by 2100, understanding historical sea level rise is imperative. This increase in sea level has the potential to displace up to 187 million people globally. Damages will exceed into the billions of dollars and the safety of coastal communities will be at great risk. Improved knowledge of historic sea level rise will significantly help reduce these potential losses. This project reconstructed sea level rise along the continental shelf since the last glacial maximum. Multibeam echo sounder (MBES) was used along with a subbottom profiler to reconstruct a continental shelf boundary adjacent to the coast. Transect lines were composed parallel to each other from 90 to 120 meters using MBES and a subbottom profiler to acquire measurements of the seafloor. These remotely sensed estimates of depth have provided evidence of a lowstand level as well as historic shorelines since the last glacial maximum. As sea levels continue to rise, understanding the history is vital to making a long term forecast for the future. Having this information will provide some insight into the extent and durability of shoreline building processes that must take place. 

The use of a fluorometer as a proxy for cell counting is a common method to track phytoplankton culture growth. A fluorometer works by emitting a beam of light, which excites the electrons in chlorophyll a, causing it to emit residual light. The fluorometer then measures the intensity and wavelength of that light. This information helps identify the relative abundance of cells present without giving a direct cell count. When conducting experiments involving the growth rate of photosynthetic cells it would be more beneficial to know the direct cell count as opposed to relative chlorophyll abundance because it is possible they may not correlate exactly as cells have the ability to adjust the ratio of chlorophyll in response to differences in light used in culturing. The marine picocyanobacteria, comprised of the genera Prochlorococcus and Synechococcus, are the most abundant photosynthetic organisms on Earth. I will culture five strains of picocyanobacteria in batch cultures using artificial seawater media in varying light and temperature conditions. I will measure the relative fluorescence of the chlorophyll a in the cultures at regular intervals throughout the growth cycle of the batch cultures. At the same time I will also measure the cell abundance using the flow cytometer. The flow cytometer will individually count and characterize the cells by chlorophyll fluorescence, accessory pigments, and cell size. My hypothesis is that the fluorescence based proxy of cell abundance measured by the fluorometer will highly correlate with the cell count from the flow cytometer, but that exact cell counts will vary under different culturing conditions. My results will be able to provide scientists who use the fluorometer as a proxy for growth a better understanding of the actual number of photosynthetic cells growing in each tube.

Bacteria play important roles in marine nutrient cycles. However, most marine bacteria are uncultured and little is known about their specific functions in marine nutrient cycles. Environmental members of the gamma proteobacterial sulfur oxidizer (GSO) clade have the genetic potential to use energy from sulfur oxidation to assimilate carbon, suggesting that they contribute to carbon and sulfur cycling in the oceans. Here we report the isolation and initial characterization of an open ocean representative from the GSO clade. Our isolate, GSO-NP4, was purified and its identity confirmed by 16S rRNA gene analyses. This isolate grows to relatively low cell densities (2 x E5 cells/ml) and has a doubling time of approximately 19 hours. Six 1L cultures were required to obtain 3.1g of DNA for genome sequencing. Six to twelve additional 1L cultures were established to obtain enough DNA to sequence the complete genome of GSO-NP4. Genomic information of this isolate is essential for future studies to determine the roles of GSOs in marine carbon and sulfur cycles.

Diatoms are unicellular photosynthetic algae, or phytoplankton, and account for approximately 20% of global primary production. The pennate diatom Pseudo-nitzschia can produce a neurotoxin called domoic acid (DA) that bio-accumulates in the tissues of shellfish when this diatom blooms. DA poisoning causes life-threatening conditions in mammals and humans when these shellfish are ingested. Parameters such as shellfish exposure length and bloom toxicity can be found by understanding what regulates these diatom communities. One mechanism of bloom regulation that we know little about is that of viral infection, despite viruses being the most abundant predator in the ocean. After a toxic Pseudo-nitzschia bloom at Sunset Beach, Oregon was sampled in 2009, the first Pseudo-nitzschia infecting virus (PmDNAV) was isolated by infecting the host P. multiseries Clnn-16. I hypothesize that there are many different viruses that can infect the genus Pseudo-nitzschia in addition to the PmDNAV. Over the past year, I worked to isolate additional Pseudo-nitzschia viruses from three blooms collected in the Pacific Northwest: Penn Cove, Friday Harbor, and Sunset Beach, Oregon. I have identified potential viruses in 12 of 48 infection experiments using these bloom samples. Three strains of Pseudo-nitzschia: GGA2, GGA3, and GGB1, which represent the species P. multiseries and P. cingulata, were infected by putative viruses from two blooms, while many others were only infected by one or none. The data suggests that independent of species, certain strains of Pseudo-nitzschia are more permissive to viral infection than others. As well, in June 2012 I isolated seven new strains of Pseudo-nitzschia from Golden Gardens, WA. I genetically identified these strains by extracting DNA, running PCR, and sequencing the Internal Transcribed Spacer region. I will test these strains to determine how permissive they are, and how effective they will be to use as hosts when working to isolate new viruses.

With the rise of atmospheric carbon dioxide, understanding the various facets of the carbon cycle is critical. In temperate coastal systems, the phytoplankton group of diatoms play a key role in the carbon cycle by sequestering carbon from the atmosphere into deep ocean sediments. Many scientists turn to laboratory culturing experiments to make predictions about the response of phytoplankton to changes in climate. But do these laboratory studies serve as realistic proxies for environmental responses? This study will compare growth rates of phytoplankton communities from Barkley Sound, British Columbia using field and laboratory experiments. Field experiments will comprise an in situ community growth rate measured using diffusion chambers in addition to on-ship incubations measuring the community growth rate in response to added nutrients. Field samples will be used to isolate the three dominant diatom species into a mixed-species culture for laboratory experiments. An analogous culture using laboratory isolates of the same species will be created, and the two cultures will be kept in a semi-continuous batch culture experiment tracking the growth rates in response to added nutrients. Comparisons of the growth rates in situ, shipboard, and in the laboratory will indicate how growth rates differ between natural phytoplankton assemblages and laboratory settings. Growth rates will be calculated using changes in chlorophyll a levels, a proxy for cell densities. If growth rates are much higher in the laboratory cultures than in the wild cultures, the implication is that there are limitations to growth in the natural environment that should be factored in when correlating laboratory experiments to the responses of natural phytoplankton assemblages. However, if there is no significant difference in growth rates between the experiments, then the laboratory conditions can provide similar conditions as in the field and laboratory culture experiments and can be easily used to predict environmental responses.

Some species of dinoflagellates develop into dormant, spore-like structures known as ‘cysts’ that sink to the sediment as a part of their lifecycle. Causes of the production of cysts include changes in water temperature and nutrient concentrations as well as sexual reproduction. Studying the role of cysts as a means of proliferation and expansion of dinoflagellate populations is an important part of understanding their place within the ecosystem. The study of cysts can strengthen our understanding of how dinoflagellate blooms can affect other populations within an ecosystem through their functions as producers and consumers as well as their roles in the global carbon cycle. If the dominant species in these blooms is capable of producing toxins that are dangerous to humans and other organisms, predicting the location and density of the blooms is vital. This study investigates the differences in concentrations and diversity of dinoflagellate cysts within the shallow sediments among Effingham Inlet, Uchucklesit Inlet, and the head of Imperial Eagle Channel in Vancouver Island, British Columbia. Sampling took place between January 22nd and February 3rd, 2013 aboard the University of Washington’s R/V Thomas G. Thompson. A comparison of the dinoflagellate cyst assemblages among the basins will be performed through the use of sediment cores, stains, and epifluorescence microscopy. The dinoflagellate cysts will be enumerated using a modified version of the method described by Yamaguchi et al. (1995). Previous studies have found variations in the composition of assemblages of dinoflagellate cysts within these basins that could be attributed to differing circulation patterns affecting the distributions and diversity of the dinoflagellate cyst assemblages. It is reasonable to hypothesize that these differences will be reflected in variations in the relative abundance and variety of cysts found in these locations.

Pseudo-nitzschia is a genus of phytoplankton widely dispersed throughout the world known for its production of a neurotoxin called domoic acid. As there is not a lot known about which species of Pseudo-nitzschia are associated with the neurotoxin, research on domoic acid is very limited. Little is known about the evolutionary relationships within the genus, but in 2002, the genus was broken into two clades (Lundholm, et al. 2002). Recently, the validity of these clades was tested by the sequencing of the Ribulose-1,5-bisphosphate carboxylase oxygenase (RuBisCO) gene in 14 species of Pseudo-nitzschia (Guannel, unpublished data). As there are currently 37 known species, the goal of this project is to sequence DNA, using the RuBisCO gene, from more species in order to fill out more of the phylogenetic tree. Cultures of 6 strains of species lacking known RuBisCO sequences were grown to mid-exponential phase and then had their DNA extracted. After the DNA was isolated, polymerase chain reaction (PCR) was conducted in order to amplify the gene. Before the DNA was sent for sequencing, the PCR products were run on an agarose gel confirming that the RuBisCO gene had in fact been successfully isolated and amplified. After the DNA is sequenced and placed on the phylogenetic tree, the physical characteristics (cell size, photopigments, etc.) of species making up each clade are then compared. This provides additional support as closely related organisms are likely to have similar traits. For example, we predicted that species with a larger cell size ( > 3 µm), would fall into Clade I, while smaller cells ( ≤ 3 µm) would be placed in Clade II. Through the addition of these species to the phylogenetic tree, further research can be conducted to pinpoint where the production of domoic acid lies in the evolutionary history of Pseudo-nitzschia.

Wildlife suffer from many ecological and biological consequences after an oil spill. The use of chemical surfactants to convert oil spills to small droplets has been the source of ongoing debate since little is known about the impacts they have on plants and animals in the ocean. Surfactants are a natural byproduct of many bacteria that are uniquely adapted to the marine environment. Our research assessed surfactant activity of cell free supernatants (CFS) from several cold-adapted bacteria using crude oil. We cultured various bacterial isolates under optimal growth conditions to ensure surfactant production was not missed. Exudates, the chemically benign “leftovers” containing the extracellular surfactants from the bacteria, were extracted from the cultures by gentle centrifugation before filtration of the supernatant through a membrane filter. The oil-spread assay was then used to determine surfactant activity from the exudates of several organisms. CFS was pipetted to the center of a small oil slick and surfactant strength was indicated by the amount of oil displaced. Some organisms with high surfactant ability were identified for further examination as candidates for environmentally viable alternatives to chemical dispersants.

Diatoms are major players in Earth’s biogeochemical cycling, accounting for approximately 20% of global primary production. Their dominance in several aquatic ecosystems is a testament to adaptations that provide an advantage in nutrient acquisition and growth. Ocean fertilization experiments have demonstrated that iron is the primary limiting nutrient in many open ocean ecosystems. This metal is critical to the functioning of numerous important proteins, particularly in photoautotrophs such as diatoms. An excess of intracellular iron, however, can cause oxidative damage to the cell. This project investigates genes related to iron metabolism in the recently sequenced transcriptomes of 21 diatoms and select outgroup species. Of particular interest are genes coding for ferritin subunits. Ferritin is a multimeric protein that serves as an iron storage unit, safely sequestering iron atoms in an oxidized state and releasing them back into the cytoplasm when iron supply is low. Ferritin in diatoms was previously thought to exist only in pennate diatoms. Here we show that ferritin-coding genes are expressed in members of every major diatom group. 13 out of 21 diatom transcriptomes contain full-length sequences, forming a clear monophyletic clade most closely related to cyanobacterial ferritins. Additionally, 7 of the 21 transcriptomes surveyed reveal two distinct ferritin genes, possibly due to an ancient duplication event. The presence of ferritin helps to explain the success of some diatom species in iron-poor waters, and our expanded understanding of which diatoms possess ferritin genes will help to predict the responses of this important group to a dynamic ocean environment.

Possession Sound is an estuary system on the North East arm of Puget Sound, where the delta of the Snohomish River is located. Along the shoreline lies a highly industrial and populated area where there are large amounts of CO2 being put into the atmosphere. Because the ocean is a carbon sink, most of the CO2 that is put into the atmosphere dissolves in the water, and as a result of the excess H+ ions the pH lowers, acidifying the water. With the lowered pH, carbonate becomes less available and it could become increasingly difficult for planktonic organisms with calcium carbonate shells to survive, possibly decreasing their abundance at the halocline (depth of rapid increase or decrease in salinity), while the planktonic organisms with silica shells could possibly thrive in this environment because of decreased predation and competition. To study this, pH data was collected using a multiparameter probe, and plankton samples, using a 20µm net and cod end, were collected at the halocline for three consecutive years in the fall (using only November data), to see if a change in pH was followed by a change in the planktonic organisms present. Quantified species include Chaetoceros, Odontella, Psuedonitscha, Barnacle nauplius, Crab Zoea, Amphipod. The pH ranged from 5.89-7.9. In the data collected, there were more planktonic organisms with silica shells when there were lower pH levels, although more data is needed to rule out other contributing factors. The working hypothesis is, as the pH levels decrease, the planktonic organisms with calcium carbonate shells will decrease.

Possession Sound is a complex estuary system branching off of NE Puget Sound. It is home to an abundance of organisms, primarily birds and mammals, and a multitude of environmental factors which influence them constantly, including the Snohomish River, tides, and anthropogenic factors. Buoy, the station we studied, is one of four stations in Possession Sound used by Ocean Research College Academy (ORCA) students to collect data on the state of Possession Sound. Its position in the Sound, at the mouth of the Snohomish River, allowed us to analyze data that is more diversified than the information from other stations. We compared dissolved oxygen (DO) and temperature trends from past years at the Buoy station. We found that in the winter of 2012, in comparison to 2010 winter data, the range was less extreme, with DO ranging from 7.58 mg/L at 8 meters and 11.02 mg/L at sea level, while winter data from 2012 showed DO being 11.47 mg/L at 0 meters and 6.91 at 7 meters. Based on our findings at Buoy we can infer that there has been a change in the seasonal conditions affecting DO and temperature between 2010 and 2012, resulting in increasingly extreme ranges of data in the water column. This suggests that DO and temperature trends could develop wider ranges of data in the future if the factors contributing to the increase in variability of the ranges of these two parameters remain prevalent.

Possession Sound is an estuarine system in Puget Sound’s northeast arm that is influenced by freshwater input from the Snohomish River. The Snohomish River carries sediments from upriver and deposits them in Possession Sound. Over the past three years, Ocean Research College Academy (ORCA) students have collected sediment samples at specific locations within Possession Sound that are analyzed by Everett Environmental Laboratory for concentrations of various heavy metals: mercury, zinc, copper, cadmium, lead, and arsenic. This area’s history of industrial development, including the Asarco Smelter in Everett 1900s, focused our attention on the lead and arsenic concentrations in Possession Sound. The purpose of this research is to discern any changes in concentrations of lead and arsenic observed at three stations within Possession Sound in the last three years. It was hypothesized that the station Buoy would experience greater fluctuations than the other two stations due to its proximity to the Snohomish River. The heavy metal concentrations are expected to be greater in the spring than during the other seasons because of increased river discharge from melting ice in the mountains, which results in increased stirring of benthic sediments. Dolphin 1 is a shallower location near Hat Island that is expected to have similar fluctuations that correlate with ice melt in the spring. Mukilteo is located farther south in Possession Sound, which would lead to a subtler influence from the Snohomish River, if any at all. Other factors that may impact the concentrations of lead and arsenic at Mukilteo include its proximity to the Mukilteo Ferry, a potential source of runoff containing toxins from human sources.

The wintering migration of marine birds in Possession Sound due to tidal influence is a complex and challenging study. Possession Sound provides habitat for the Pacific Flyway migration of marine birds, and the dynamic estuarine environment influences distribution of these birds due to tidal variation. The working hypothesis of this study was that birds were more active feeding during high tides in the morning hours. The data collected for this study was done by land surveys and small vessel trips along transects on North Jetty Island near the Port of Everett. The species of interest included Bald Eagles, Buffleheads, Common Loons, Double Crested Cormorants, Northern Pintails, and Pigeon Guillemots. The status of recovery from the Washington Department of Fish and Wildlife was compared to data collected. Preliminary data suggests that high tides influence the sandy substrate in Possession Sound, which provides optimum feeding grounds for Buffleheads, Northern Pintails, and Pigeon Guillemots as they have been observed more frequently.

Possession Sound, an estuary system located at the mouth of the Snohomish River in Everett, Washington, is home to a large group of industrial sites which greatly influence the types of runoff affecting the ecosystem. Industrial sites often output heavy metals, which can be dangerous at certain levels, as determined by the Environmental Protection Agency (EPA). Possession Sound is home to three primary industries with historical evidence of leaching copper, lead, and arsenic into the ecosystem: the Everett Naval base, the Kimberly-Clark paper mill, and American Smelting and Refining Company (ASARCO), respectively. We hypothesize that higher levels of these heavy metals will be found in areas close in proximity to the aforementioned industrial sites and combined sewer outfalls. To show these correlations we utilized Washington Department of Ecology 2009 data in conjunction with independent heavy metal sampling at two additional locations: one location offshore, near the historically influential sites and another two nautical miles westward, away from the shore. After collecting samples with a Ponar grab, they were analyzed for heavy metal concentrations through the Everett Environmental Lab per EPA approved methods. Results have shown high concentrations of heavy metals terrestrially, which has caused mandated cleanups of the area. Marine sampling demonstrates a seasonal trend. The concentrations of heavy metals are higher in the spring, correlating with a higher river discharge. Other variables that contribute to these trends include dredging of the river. Should concentrations of heavy metals in the sediments in Possession Sound reach levels deemed unsafe by the EPA, the health of the local aquatic ecosystems may be put at risk through bioaccumulation, particularly near industrial sites.

The fact that hydrogen isotope deuterium/protium (D/H) ratios in algal lipids co-vary with their surrounding water D/H ratios is well established. Paleoclimatologists have taken advantage of this relationship in their compound-specific D/H analyses, but little is known about the individual environmental parameters, such as temperature, salinity, light levels, and nutrient concentrations that influence D/H fractionation, or the state of unequal isotope composition. Laboratory experiments conducted with batch cultured green algae, Eudorina unicocca and Volvox aureus, grown at temperatures of 15°C and 25°C suggest that there is increased fractionation with increased temperature. The work presented here aims to elucidate the magnitude of D/H fractionation in a natural population of algae where temperature is the primary environmental variable. To test this relationship, surface water was sampled from Lake Washington once a month for one year, with a surface temperature range from ~8°C in February to ~24°C in August. Phytoplankton were filtered from the water and lipids are extracted and analyzed by gas-chromatography isotope ratio mass spectrometry (GC-IRMS) to determine the extent of D/H fractionation. We found that there was a positive correlation between temperature and D/H fractionation, in which fractionation increased with increasing temperature. The results from this research, as well as the results of similar experiments with other environmental parameters, will give paleoclimatologists accurate modern-day calibrations to apply to the analysis of lipids extracted from sediment cores in order to reveal climatic variations for the past.

Possession Sound is a smaller estuary within the northeast arm of Puget Sound, with influence from the Snohomish River. As a result of the watershed runoff into the Snohomish River, fecal coliform and other bacteria are present in the Possession Sound water column. We hypothesized that the most fecal coliform and other bacteria would be found at the surface and halocline (the zone of rapid increase in salinity) of the water column. The density difference would therefore trap the bacteria in or above the halocline. Low salinity surface water from the Snohomish River is the vector of fecal coliform due to warm-blooded animals. To determine the distribution of fecal coliform and other bacteria we referenced historical data from past State of Possession Sound (SOPS) cruises collected by Ocean Research College Academy (ORCA) students at the research station Buoy. The location Buoy is near the Snohomish River and therefore has a strong influence from the river discharge. We tested for fecal coliform at North Jetty (NJ) another location near the river. Using a sediment grab we collected samples of sediment and tested them for fecal as well. River discharge and watershed runoff change seasonally, affecting the depth and strength of the halocline so we categorized the data by season in order to find any correlation. The data shows during times of strong stratification, only a single fecal coliform at the surface, whereas an average of twenty other bacteria colonies were found at the surface. At the halocline there were no fecal coliform, but on average four other bacteria. In the deep layer there were no fecal coliform and on average two other bacteria found. The seasonal analysis of the same data demonstrates that fall months had the highest concentration of other bacteria and winter contained the most fecal.

Over the past decade, measurements of hydrogen isotopes of lipid biomarkers, in particular leaf waxes, have been used to reconstruct past climate change. This method is appealing because lipids are well preserved in sediment and their hydrogen isotope ratio is primarily controlled by the hydrogen isotope ratio of their source water, which itself is controlled by factors such as precipitation amount and temperature. However, it has been shown that the isotopic difference between source water and lipids is distinctive among different plant species. In particular, it has been shown that salinity strongly affects the hydrogen isotope ratio of lipids produced by mangroves, but the mechanism that controls this relationship is unknown. Plants, including mangroves, take in water mainly from surrounding source water, but the deuterium to hydrogen ratio within the plant may be impacted by differences in transpiration rate, photosynthetic rate and respiratory water production. The photosynthetic rate (mol CO2 m-2s-1), internal carbon, (μmol CO2/ mol air) and conductance (mol H2O m-2s-1) of three species of mangrove, Rhizophora apiculata, Avicennia germinans, and Xylocarpus granatum, were measured at six different salinities from 5 to 30 ppt. The date, time, and leaf number were also recorded as additional measurements. Determining whether salinity, time of day and/or differences among species affects photosynthetic rate, internal carbon, and conductance is important in comparing the biosynthetic pathways of the three species of mangroves. It will allow us to investigate the cause of increased deuterium discrimination in mangroves at high salinity.

In the Puget Sound marine ecosystem, a large estuary complex located in the Pacific Northwest, plankton species are impacted by both seasonal variations and water chemistry. Salinity and pH data are collected monthly by Ocean Research College Academy (ORCA) students during State of Possession Sound (SOPS) trips, near the urban center of Everett and the Snohomish River delta. We studied salinity and pH data in parallel to plankton samples collected in a vertical tow by a 20µ plankton net. By collecting these data at different stations within the Possession Sound subsystem, we are able to compare varied salinity and pH data to account for spatial differences, in tangent with the collected plankton samples. We focused on Coscinodiscus spp.,  Pseudo-nitzschia spp.,  and adult Copepoda spp., for our plankton species, as they were typically the largest populations in every cruise. The data we collected showed that plankton were most numerous within water of a pH between 6.3-6.7 and a salinity of 28ppt-31ppt. Samples collected that strayed from the 6.3-6.7 pH range or went above or below 26-31ppt had either no, or significantly fewer amounts of plankton.