Imidacloprid (IMI) may be a viable alternative to carbaryl for controlling burrowing shrimp (Neotropea californiensis) that destabilize sediments resulting in poor survival and low yields of the commercially harvested Pacific oyster (Crassostrea gigas). Previous laboratory tests indicate the shrimp are overtly affected (immobile, cannot burrow) when exposed to IMI in sediment pore water, but are not killed. These results contrast sharply with observed efficacy in the field, i.e. mortality 72-96 h post application and subsequent reductions in burrow counts. Understanding the factors governing efficacy in the field may improve control. We exposed 11 adult female shrimp that had burrowed within 30 cm of native sandy sediment to each of four concentrations of IMI (Nuprid® 2F) for 96 h: 6, 30, and 150 ppb active ingredient. We compared the response of these shrimp to that of 10 negative controls. Surface water (10 cm) was exchanged with clean seawater (salinity=30 ppt) 6 h post dose and then twice daily simulating tidal exchanges. Behavior and water quality were monitored once daily. All shrimp in the IMI exposures were overtly affected and mortality was dose dependent: 0 ppb (0%), 6 ppb (9%), 30 ppb (27%) and 150 ppb (82%). The LC50 was 51 ppb (95% CI=24-146 ppb). Mortality at 150 ppb occurred 30-54 h post dose; mortality at lower concentrations occurred between 54-78 h. Shrimp that survived the highest doses were closest to the surface when immobilized where dissolved oxygen (DO, % saturation) was greatest. Immobilized shrimp were unable to maintain their burrows, the burrows subsequently collapsed, separating them from the DO within the surface water, resulting in asphyxiation. Results suggest the shrimp can tolerate very low dissolved oxygen within sediment without IMI, but their sensitivity to IMI increases due to factors associated with their impaired ability to maintain burrow integrity and circulate water.

Marine debris is a prevalent form of environmental pollution in which man-made products are released into oceans and waterways. Debris objects pose a variety of concerns, including entanglement and ingestion by wildlife, toxicity, and introduction of invasive species (biofouling). The Coastal Observation and Seabird Survey Team (COASST), a citizen science program at UW, is currently developing a marine debris monitoring protocol. The protocol calls for field surveys documenting basic site characteristics and attributes of debris objects. Seventeen attributes were chosen as indicators of potential harm to wildlife (e.g. loop presence and bite marks), invasive species threat (biofouling), and debris movement patterns in the ocean (e.g. size, material). Our team analyzed images from a database of over 5,000 marine debris photos collected by COASST at over 200 beach sites in the Pacific Northwest and Alaska. We utilized an iterative approach with two students independently assigning attribute states (e.g. color: black, bite marks: yes) to debris objects from 900 randomly selected photos. We compared results to understand likely sources of human error. Initially, we found that color, malleability, geometric shape, material, intactness, and weathering were attributes that posed the greatest challenges – where surveyor disagreement (error rates) exceeded 15%, with some approaching 50%. After three rounds of result analysis and attribute definition refinement only 5 of the 17 attributes had error rates exceeding 15% (range 16-30%), reducing the likely error volunteers will make. The resultant standardized attribute definitions and state assignment protocol will provide a means of collecting reliable (i.e. low error) baseline abundance and distribution marine debris data as well as risk assessment based on specific attributes of use for further research, conservation endeavors, and resource management.

 Snailfishes of the genus Careproctus are known to deposit egg masses inside the gill cavity of lithodid crabs. Identification of the species responsible has been inconclusive due to the difficulty associated with identifying snailfish eggs or larvae to species. DNA samples were collected from egg masses found in crabs both in the commercial golden king crab (Lithoides aequispinus) fishery and during survey work conducted by the Alaska Fishery Science Center. Egg masses were found in both golden king crabs and scarlet king crabs (L. couesi). Cytochrome Oxidase I (COI) was amplified from egg mass samples and sequenced. Comparison of COI sequences from eggs with COI sequences from positively identified adult vouchers yielded identification of 75 egg masses to species: 38, 29, 7, and 1 egg masses were identified as Careproctus rastrinus, C. colletti, C. furcellus, and C. simus, respectively. Egg masses were determined to contain eggs from only one species. These results are the first positive identification of the snailfish species responsible for laying egg masses in crabs. Identification of species involved may be useful in further attempts to classify the nature of this relationship between snailfishes and crabs.

Recovery of the Pacific Northwest native Olympia oyster (Ostrea lurida) population after a near-collapse in the industry has been slowed due to several factors. Though no longer the prominent oyster along the west coast of North America, the Olympia oyster remains an important commercial, cultural, and ecological species. Effective conservation efforts are dependent on understanding the oyster’s physiology and distribution. Establishing detailed genomic resources is crucial to enhance effective management of the Olympia oyster. This study aims to extend existing research on the Olympia oyster transcriptome by characterizing the gonadal transcriptomes male and female oysters. Resulting contig sequences were compared with ProtKB/Swiss-prot database and further annotated with Gene Ontology associations. Furthermore potential genetic markers were identified. These resources add to genomic tools available for future conservation of Ostrea lurida and provide novel insight into reproductive function in bivalves.

Ocean acidification resulting from increased partial pressure of carbon dioxide (pCO₂) in seawater (due to increased atmospheric CO₂ levels) lowers seawater pH. Declining seawater pH dissolves shells and increases mortality of many shellfish. The risk of losing oysters is discouraging not only because of their influence on biodiversity, but also because of the economic importance to the shellfish industry. By studying the optimal growth conditions, the Friedman lab has been able to look at whether it would be feasible to grow Pacific oysters under present day or elevated pCO₂. To do this we raised groups of oysters in either high or low pCO2 levels and observed their mortality and overall growth. We have found that the oysters raised in the highest pCO₂ levels as well as those whose parents were raised in low pCO2 levels but were themselves raised in high levels had the highest mortality, while the oysters in the lower pCO₂ had lower mortality.

 I studied whether Chinook parr can tell the difference between full and half siblings based on their olfactory senses. 800 total parr were tested with four different female parents and the same male parent using a Y-maze device that allowed them to ‘choose’ the smell they preferred during the months of March and April 2014. The hypothesized results are that full siblings are recognized over half-siblings. If Chinook prefer their siblings over their non-siblings they are more likely to have a higher survival rate and lower predation rates because they will be less likely to be aggressive and cannibalistic, and more likely to school with these siblings

The U.S. food system has been de-localized from decades of industrialization and globalization. There have been many environmental and social repercussions, including loss of farmland, devaluing of farmers, loss of food sovereignty, and a consumer disconnect. How can we support a strong local food economy and shorten the distance from farm to table? Organizations and agencies play a key role in facilitating the increasingly popular local food movement in the Puget Sound region. The purpose of this project was to analyze the capacity and affinity of each group, and investigate how a communication network could lead to greater success. My internship with American Farmland Trust researched these groups and organized them based on focal area. This served as a preliminary effort to map the overarching shared goals of the movement. Supplemental research was conducted through an extensive review of published literature and interviews. The results suggest that defining the “center” of the movement through a formal communication network and regional planning will increase overall success. Additionally, there are severe gaps in the local food supply chain and excessive emphasis in other areas that could be reallocated to better serve the broader community. A local food system with strong coverage from farm to table is imperative for the future of sustainability and food security in the region, and similar efforts elsewhere could serve to strengthen food systems nationwide.

River-dwelling organisms inhabit ecosystems characterized by an assortment of habitats that vary in their nutrient availability, temperature, flow, food resources, and risk to predation. Specific habitats rarely offer the optimal conditions for all of these variables so mobile organisms typically use habitat combinations that offer complementary risks and benefits. I hypothesize that tributary junctions within river networks are particularly profitable for fish because they offer complementary resources across small spatial scales. To test this hypothesis, I conducted snorkel surveys during the heat of the day around nine tributaries divided equally among three spatial segments in a river system in Idaho. Each river segment displayed a varying degree of historically active wildfires and provides a mosaic of heterogeneity in riparian cover and nutrient inputs. Fish were counted downstream and upstream of tributary junctions to obtain a total density per stream reach area. Nitrogen and phosphorous concentrations of incoming tributary water were measured as a proxy of primary productivity in each environment. I also measured water temperature at tributary junctions to quantify potential temperature gradients for fish to use as a thermal refuge. My preliminary results suggest that fish tend to aggregate at the junctions of tributaries that are different in temperature and nutrient status from the main stem. As climate changes, it is important to understand how river networks provide prosperous options for fish. My work will hopefully contribute to efforts designed to prioritize river habitats for protection and restoration.

Variation in river flow results in the expansion and contraction of the main channel, off-channel habitat, and the physical connections between these components. Hence, rivers are characterized by a mosaic of habitat conditions that shift across space and time. Here, we explore how a stream-dwelling fish integrates across spatial and temporal shifts in the availability of thermal and trophic resources. Across multiple years of variable flow, juvenile coho salmon (Oncorhynchus kisutch) have been observed feeding on an ephemeral food source in the cold main channel at night; returning to warm off-channel habitat during the day where their ability to metabolize large meals is greater. We hypothesize that an analogous tracking strategy is used to take advantage of in-situ prey and a shifting distribution of thermally optimal habitat within a single season. During the early summer in southwest Alaska, high lake levels flood the lower reaches of a third-order stream. As summer progresses, lake levels subside and the spatial distribution of thermal resources and connectivity of habitats within the stream is reduced. Preliminary analysis shows that juvenile coho prey heavily on stoneflies, which are concentrated in the cold main channel. Using snorkel surveys, PIT tagging, and gastric lavage, we will monitor changes in the spatial distribution and diet composition of fish over the course of a day and a season. We will compare these observations with changes in the distribution of warm habitat – recorded by i-button temperature loggers – to assess the ability of coho to integrate across shifts in resource availability. We aim to document the frequency of resource tracking in juvenile coho during this early summer period. The results have implications for understanding the importance of environmental complexity to endangered salmon populations and associated species in systems where humans have homogenized floodplains.

The role jellyfish play in marine food webs is not fully understood. We investigated whether the trophic level of lion’s mane jellyfish varies with size, month, and type of tissue sampled in an individual. To investigate these questions, we used stable isotope analyses to trace the values of 13C and 15N. We found that isotopes do not change with size or month, and the effect of tissue type is unclear.