Possession Sound is a salt-wedge estuary influenced by both sea water entering through the Puget Sound and fresh water entering from the Snohomish River. Regionally, upwelling off the Pacific Coast during spring and summer months brings acidic deep water into the Puget Sound. Locally in the Possession Sound, previous research has shown that seasonal cycles in both temperature and river discharge are the primary influencers of pH. These cycles are affected by the El Niño Southern Oscillation (ENSO) climate pattern, which alternates between a cooling phase (La Niña), a warming phase (El Niño), and a neutral period. The biological processes of many organisms are influenced by pH levels, and few studies have examined interannual pH variation in estuaries. This study seeks to identify the influence of ENSO on pH cycles in two different areas of Possession Sound, based on proximity to the Snohomish River. Surface pH and temperature data were analyzed at two sites, Buoy (closer to the river) and MBT (farther from the river) from January 2010 to September of 2017, using Yellow Springs Instruments and a Niskin Bottle. River discharge data was ascertained from United States Geological Survey data recorded near Monroe, Washington (2010-2017). The hypothesis of spatial variability in pH due to proximity to the river was not supported. Many of the trends at Buoy were the same or more pronounced at MBT, suggesting that the influence of the Snohomish River at Buoy did not make that site more sensitive to ENSO than MBT. Surface pH was more variable at MBT than at Buoy during the summer months, presumably due to eutrophication and subsequent decay during periods of intense biological productivity. Future studies are planned for seasonal variations of biological factors along with dissolved oxygen variation with depth to further analyze these pH trends.

The Puget Sound is a complex estuarine system within the Salish Sea, fed by both high salinity water from the Pacific Ocean and freshwater from a number of rivers. The Snohomish River is the second largest input, transporting freshwater from the Skykomish and Snoqualmie rivers to Port Gardner Bay off the coast of Everett. At its mouth, the higher density salt water from the Puget Sound intrudes into the freshwater, forming a salt wedge that causes a highly stratified water column which rapidly changes with the tidal cycle. These mixing dynamics may be the primary driver of biological productivity in the estuarine system. To characterize the density profile relative to tidal patterns and season, current speed and velocity were recorded utilizing a Nortek ADCP. During normal outflow (3,500 f^3/s) of the Snohomish River, upward velocities were positive during flood tide and negative during ebb tide, following a typical salt-wedge trend. During a peak outflow event (56,000 f^3/s) on October 22nd, this tidal cycle dependence was disrupted and downwelling dominated in the form of negative vertical velocities throughout the water column. In addition, the magnitude of east/west velocities increased during peak outflow. This signaled a period of intense turbulence at the bottom of the water column. During the same time span, data concerning turbidity and chlorophyll levels were recorded utilizing a Seabird CTD. No clear trend was evident in chlorophyll levels at both normal and peak outflow timespans. Turbidity maintained high levels (35 NTU) following peak outflow, possibly reflecting the transportation of sediment from the river bed into the water column. This transportation would be caused by the turbulence reflected in the higher magnitude of the east/west velocity data.

Some of the most widely used medications have unknown side effects on wildlife after disposal. One of these compounds is 17α-ethynylestradiol (EE2), a potent synthetic estrogen and endocrine disrupting compound. EE2 is an active ingredient in birth control pills and has been found in environmentally relevant concentrations in waterways due to the inability of wastewater treatment systems to completely remove it. Even at parts per-trillion, EE2 can cause male fish to develop female sex organs in a process known as intersex. EE2 mimics estradiol, the natural female sex hormone that causes feminization, and affects reproduction and development. Another role of estradiol is it binds to estrogen receptors on cells to modulate immune responses. Our group has observed increased mortality rates in fish exposed to EE2 prior to pathogen challenge. Additionally, we have shown that EE2 down regulates genes and pathways involved in innate immunity in fish, some of which are tied to phagocytosis, a process essential for ridding the body of pathogens and cell debris. Therefore, altered phagocytosis rates may be contributing to the increased mortality of fish when they are exposed to EE2 and challenged with pathogens. My hypothesis is that EE2 alters phagocytosis. To test this hypothesis, I’ve developed an in vitro phagocytosis assay using a rainbow trout macrophage cell line (RTS11). In this assay, RTS11 cells are cultured with fluorescently tagged bacteria that only fluoresce when eaten by phagocytic cells. Cells can be cultured in the presence or absence of endocrine disrupting compounds with potential changes in phagocytosis being measured using a flow cytometer and associated statistics to assess if a compound alters phagocytosis—a key component of innate immunity. This study will provide insight into the biological mechanisms that contribute to higher mortality rates in fish exposed to EE2 prior to being infected with pathogens.

Prevention of aquatic invasive species transmission by recreational fishing and boating is a fundamental management challenge. These activities can entrain non-native plants and animals via tangled lines, bait buckets, or hull encrustation, leading to introductions into new waterbodies. With hundreds of millions of people participating in fishing trips each year, understanding angler movement behavior can provide critical insight into the most effective locations and scales at which to apply preventative measures. Angler behavior is often inferred from infrequently and sparsely conducted surveys that provide limited spatial and temporal insight into this challenge. Here we capitalize on a big data opportunity provided by ReelSonar’s recently launched iBobber, a sonar-enabled bobber with over 3,000,000 records of fishing location, water depth, and environmental variables collected over three years. By quantifying geographic patterns of fishing activities and assessing how these patterns change seasonally, we explore angler behavior in terms of fishing frequency and distance traveled between sites, and characterize the attributes of fished ecosystems. Our study offers novel insight into spatiotemporal patterns of angler behavior and carries important implications for predicting and preventing future transmission of aquatic invasive species via recreational fishing.

Phytophthora alni is a species complex of pathogenic oomycetes (water molds) that can cause lethal disease in alder trees, Alnus spp. One variant, P. alni subsp. alni, is widespread across Europe, devastating stands of alder since the 1990s. One less lethal member of the species complex, P. alni subsp. uniformis, has already been found in the wild in Alaska and Oregon, but not in Washington State. Recently, it has been detected in potted alders in nurseries in Pierce County. It is currently unknown whether any member of the P. alni species complex is in the wild in Washington, either naturally or through introduction from nursery plants. To begin efforts to detect Phytophthora alni in Washington State, a risk assessment map will be created using Geographic Information System (GIS) techniques. The spatial analysis will involve examining the environmental factors that increase infection susceptibility, such as slope, soil grain size, and flooding, and correlating with the distribution of alders. Important questions that could be revealed are whether high risk areas are upstream, where infection could spread, or downstream, and whether high risk areas correlate with urban or agricultural land use. The risk assessment will provide a starting point for choosing sampling sites, which is the next step in detecting the existence of P. alni. Additionally, the final analysis will inform forest management practices, as the highest risk areas could be inspected for symptomatic alders and mitigation measures could be enacted if any are found. The assessment will also have implications for restoration sites, where native trees such as alder are planted from nursery stock.

From November 2015 through March 2016, the Olympic Mountains Experiment (OLYMPEX) field campaign was conducted on the Olympic Peninsula to study how wintertime precipitation is modified as it passes over coastal mountains and to validate satellite-derived precipitation measurements from the U.S.-Japan Global Precipitation Measurement (GPM) mission. This project uses OLYMPEX data to explore the topographic effect on these Pacific frontal systems by examining cloud and precipitation structure on the leeward side (usually northeast) of the Olympic Mountains, where there is typically a minimum in precipitation relative to the windward side. While most research has focused on the structure of the windward side, this study uniquely examines the leeward side of the mountains. A radar managed by Environment and Climate Change Canada on Vancouver Island provided measurements of the vertical structure of the frontal systems over the northern Olympic Mountains, including intensity inferred from radar reflectivity. Using environmental data from NCEP North American Regional Reanalysis on the windward side (usually southwest) of the mountains, this study classifies the leeward radar data based on upstream synoptic conditions. It then examines the cloud and precipitation structure on the leeward side of the mountains in various atmospheric environments. Preliminary findings of this study reveal, for example, that the intensity of cloud systems on the leeward side is dependent on upstream stability. Locally, these findings will inform studies of snowpack and water supply as many reservoirs depend on precipitation that occurs on the leeward side. Outside of the Pacific Northwest, these findings can be applied to other midlatitude coastal mountain ranges on the west side of continents around the world.

As general circulation models (GCMs) increase in complexity, the number of physical processes representing the climate system increases. A central goal of climate science is to understand how uncertainty in these physical processes, translates into uncertainty in the system response. But the very complexity of the GCMs generates a troublesome question: how do you properly define a stable and unchanging reference system with which to compare constituent elements and characterize their uncertainties? To navigate around this, we introduce a simple energy balance model (EBM) that accounts for the transport of both sensible and latent heat in the atmosphere. We demonstrate that the EBM accounts for approximately 90% of the inter-model spread in the temperature response for an ensemble of GCMs subjected to increasing CO2. We then calculate the unique model patterns of ocean heat uptake, radiative forcing, and radiative feedbacks and demonstrate that 100-years after an abrupt quadrupling of CO2 above preindustrial values, the largest source of uncertainty is the pattern and amplitude of radiative feedbacks. Using this, we identify regions of high feedback uncertainty and show how this can bias temperature responses in other regions.