Eelgrass beds in central Salish Sea are critical components of healthy ecosystems that are vulnerable to anthropogenic impacts. This study utilized two locations in Possession Sound to monitor water chemistry within and near two different eelgrass beds; one unmapped, and one established. The study compared these two locations and investigated the impact of location on water chemistry within the bed. Data-sharing and collaboration with the Samish Indian Nation Department of Natural Resources’ work on eelgrass beds in Fidalgo Bay provided a broader scope into regional differences within the central Salish Sea. This study was conducted by Ocean Research College Academy (ORCA) students at eelgrass beds in Possession Sound located near Mukilteo and Hat Island. The study ran from October 2019 to spring 2020, and utilized background data from past studies to inform studies at the bed near Mukilteo. Data were collected using a combination cast of a camera collecting visual data and a CastAway CTD, which collected vertical profiles of salinity and temperature at recorded geographic coordinates. Data were collected during a free drift across the eelgrass bed. An EXO Sonde was temporarily installed in the bed to collect chlorophyll and turbidity data in a longitudinal manner. The study primarily explored how location impacts the water chemistry eelgrass beds in central Salish Sea both within the bed and within a region. Research going forward could study remote beds more comprehensively using technology previously tested such as drones and SONAR, as well as a longer-term collaboration between the Samish DNR and ORCA.

In Spring of 2018, I helped collect a 45 cm sediment core from San Blas Basin on the continental shelf of pacific México, 50 km off the coast and north-west of Puerto Vallarta. After noticing that there were large sticks and seeds in the sediment, our Méxican collaborators gifted me the core to analyze lignin, a biomarker for terrestrial organic matter (TOM). Sticks in oceanic mud 50 km off the coast is unusual so we were excited to find out this geological story. I found that the total amount of lignin phenols ranges between 1.5 to 4.5 mg lignin phenol/10 g sediment except for an order of magnitude increase between 18 cm and 26 cm which was 20 to 40 mg lignin phenol/10g sediment. Acid to aldehyde ratios of vanillin-type lignin (Ad/Al (v)), a proxy for degradation, had a range of 0.36 to 0.58 while the section between 18cm to 26cm was fresher with a range of 0.26 to 0.28. S/V to C/V analysis indicated that the lignin is sourced from angiosperms. The section between 18 cm to 26 cm had statistically similar values ranging between S/V of 0.85 to 0.95 and C/V of 0.19 to 0.21. S/V to Ad/Al (v) analysis had a negative slope indicating S-type lignin is preferentially degraded and the background lignin signal could look more like the fresher 18-26 cm section if degradation had not occurred. My lab partners, Méxican collaborators, and I conclude that a large flooding event brought fresh TOM off of the land and the sediment deposition and deposited 8 cm of sediment in one event due to the S/V and C/V values overlapping. The flooding was likely a tsunami, large hurricane, or flash flood from the nearby Santiago river.

As anthropogenic climate change progresses it is drastically altering the health of watersheds globally. In efforts to mitigate changes to marine ecosystems, many studies are using physical and chemical measurements to inform plans and create legislation. The impacts of climate change on local ecological communities are harder to track and take longer to show themselves which is why it is vital that we develop accurate techniques for measuring this kind of change quickly. This project, completed as part of Puget Sound Foraminifera Research Project at the Burke Museum, uses calcareous benthic foraminifera recovered and identified from sediment samples collected by the Washington State Department of Ecology between 2017 and 2018. Benthic foraminifera are marine protists that live on or within sediment and form shells of calcium carbonate or agglutinated sand grains. Foraminifera used in this project were stained with Rose Bengal to ascertain whether they were alive at the time of collection and grouped according to World Registry of Marine Species protocol. Stained and unstained individuals were counted to create living and dead assemblages. The goal of this study is to determine the validity of using total assemblages that include both living and dead foraminifera as a proxy for quantifying the living assemblages in Puget Sound. This is important because previous research has found discordance between living and total assemblages of molluscs, pteropods and ostracods in embayments heavily impacted by anthropogenic activity. This study includes 5 embayments in Puget Sound. Results from Bellingham Bay and Sinclair Inlet suggest that the validity of using total assemblages as a proxy for living assemblages may vary across different areas of Puget Sound; while the total assemblage and living assemblage matched in Bellingham Bay, Sinclair Inlet has been found to have significantly different total and living assemblages.

The Snohomish River Estuary, a salt-wedge estuary in Possession Sound and the central Salish Sea, is predisposed to the development of low-pH conditions due to multiple biogeochemical processes, such as water column circulation, seasonal upwelling, freshwater influences, and anthropogenic stressors from the Everett region. Tracking the influence of freshwater sources on temporal pH trends in Possession Sound is key to understanding the effects of ocean acidification on the Snohomish River Estuary. The study was conducted through the Ocean Research College Academy (ORCA), a high-school and community college dual-enrollment program, which enables students to build upon long-term datasets collected by the program since 2007. To investigate ocean acidification effects, ORCA students deployed YSI 650 and EXO Sonde probes at four sites throughout Possession Sound to gather vertical profiles of pH, temperature, salinity, and dissolved oxygen from 2007-2020. River discharge data from the U.S. Geological Survey’s (USGS) Monroe, WA station were used to measure freshwater influence.. Freshwater pH, temperatures, conductivity, and dissolved oxygen from various sites around the Snohomish River Basin were taken as reference from the Snohomish County Surface Water Management Group’s open source water quality data. It was hypothesized that decreases in pH would be observed between 2007 and 2020 in addition to seasonal decreases in pH when river discharge was higher. Upwelling in late summer and early fall was expected to correlate with pH decreases. Results show that pH did not change significantly between 2007 and 2020. There was a correlation between pH and river discharge; however, pH values increased during times of higher river discharge, which does not support the hypothesis. Future research would investigate pH conditions in relation to marine influences from the Pacific Ocean to test for a more significant correlation than with the Snohomish River.

Urban stormwater runoff transports thousands of potentially toxic chemicals, metabolites, and degradation products to fish habitats. While certain contaminants, including metals and petroleum-derived compounds (e.g., polycyclic aromatic hydrocarbons) are known to adversely affect fish health, many others are unidentified and/or uncharacterized. Despite this uncertainty, green stormwater mitigation methods such as bioretention, the filtering of stormwater through a medium such as sand and compost, have recently been shown to be highly effective in terms of both reducing pollutants and improving water quality for the health of fish. However, the scope of this research to date has been limited to a small number of engineered media types. Here we used the embryonic zebrafish (Danio rerio) model to evaluate the impacts of urban arterial runoff, before and after filtration through several novel types of bioretention media. Measured toxicity indicators included eye and pericardial area, body length, and the expression of the biomarker gene cytochrome p450-1A (cyp1a). Untreated runoff from multiple storms was consistently toxic to zebrafish embryos. Conversely, each of the morphological and molecular health indicators was positively influenced by bioretention treatment. Our results indicate that bioretention compositions beyond the sand-compost mixture used in Washington State are promising in terms of reducing or eliminating near-term (i.e., acute) toxicity to fish. This expands the potential toolbox for site-specific pollution removal using green infrastructure methodologies.

Seabirds are often used as markers of ecosystem health due to their heavy dependence on the base of the food chain. The Alcidae family consists of small, diving birds who feed exclusively within the water column and rely on the sea year-round. Because of this, many view alcids as the only “true” seabirds. A research apprenticeship at UW’s Friday Harbor Laboratories on the pelagic ecosystem, Pelagic Ecosystem Function, has observed all seabirds since 2004, with consistent data since 2013. Alcids have been largely ignored in previous Pelagic Ecosystem Function studies, as the Common Murre (Uria aalge) artificially inflates the alcid family data due to their high abundance within the San Juan Channel. Upon removal of this species, it is found that non-Common Murre alcids are declining at a higher rate than any other seabird family within the channel, with a near-linear decline since 2013. In order to investigate the leading drivers of population decline, variables regarding food availability and habitat were collected in the form of chlorophyll, photosynthetically active radiation, and sea surface temperature. Compelling correlations were found between non-Common Murre alcid density and photosynthetically active radiation, as well as between chlorophyll and sea surface temperature. The data presented here is important not only for the mitigation of local ecosystem degradation, but also due to the consistency with global trends of seabird populations.

Along the shoreline of Possession Sound, located in the southern basin of the Salish Sea are 10 outflows of combined sewage systems. Combined sewage systems collect rainwater, untreated domestic sewage, and industrial wastewater within a single sewer line. When heavy rainfall occurs, these systems overflow and are directed into designated combined sewage outflows (CSOs), which then empty into the estuary, releasing E. coli (Escherichia coli) directly into the estuarine ecosystem. These CSOs, along with other factors, change the pH of the waters within the basin. Preliminary analysis of primary literature suggests a relationship exists between pH and E. coli growth. The pH change affects the enzyme growth within E. coli. As river discharge fluctuates, so does the amount of outflow from the CSOs which then cascades into pH changes at the site closer to the CSOs. The guidelines and regulations in place today allow for significant volumes of sanitary waste to be overflowed into marine systems. When river discharge increases, the overall pH within the Sound decreases. It was hypothesized that when there is a large amount of rainfall that leads to heavy river discharge and low pH, there will be more Escherichia coli growth at all of the sites throughout the Sound. Ocean Research College Academy students collected bacterial sample data at 12 stations in Possession Sound from 2009 to 2019. All data were recorded with distance from a CSO. A Niskin bottle was deployed at the surface and halocline with a YSI 650 testing pH. Samples were tested for bacterial count and compared with other samples taken after heavy rainfalls. Further research will define the trends in river discharge, pH and E.coli for Possession Sound.

As climate impacts are amplified in the nearshore regions, the Possession Sound located near the heart of the Salish Sea is a key study area of the local marine ecosystem. Systems such as these are very sensitive to fluctuations in temperature. For example, in 2015, “The Blob,” which was a massive body of abnormally warm water that ranged from California north to Alaska, raised salinity and lowered DO causing high mortality rates in a range of taxa. Events such as these are referred to as Marine Heat Waves (MHW). In 2019 analysis of satellite thermal imagery data concluded that another Marine Heat Wave had struck the West Coast displaying temperatures reaching as high as seven degrees Fahrenheit above average. Additionally, parts of the Salish Sea have observed some possible influence of the MHW from the Pacific. In order to determine the localized impact of these Marine Heat Waves, I used data from a fixed CTD probe from the Ocean Research College Academy were analyzed, focusing on parameters temperature, salinity, and dissolved oxygen. I hypothesized that there is a delay of increased temperature from the Pacific due to possible mixing of coastal currents traveling through the Juan de Fuca Strait into the Salish Sea. When exploring this data set, I have found that since 2009 average water temperatures have risen, 2019 average temperature is .4 degrees higher than in 2009, with 2015 having a peak temperature average of 11.5 degrees Celsius, 1.1 degrees higher than 2009, which aligns with “The Blob” of 2015. Trends have shown an increase in average temperature since 2009, with MHWs event being a prevalent factor in rising average temperatures, and lower dissolved oxygen averages.