Anna N. Kagley

Increased Susceptibility of Juvenile Chinook Salmon to Vibriosis after Exposure to Chlorinated and Aromatic Compounds Found in Contaminated Urban Estuaries

Abstract Saltwater-adapted juvenile chinook salmon Oncorhynchus tshawytscha exposed to aromatic and chlorinated compounds, representative of contaminants found in urban estuaries in Puget Sound, have a higher susceptibility to vibriosis than do fish exposed only to the solvent vehicle. Susceptibility to vibriosis was assessed by examining the percent cumulative mortality of the salmon after exposure to the bacterial pathogen Vibrio anguillarum. The aromatic and chlorinated compounds examined consisted of a sediment extract from the Hylebos Waterway that was enriched in butadienelike compounds (chlorinated-enriched Hylebos Waterway sediment extract (CHWSE)), a model mixture of polycyclic aromatic hydrocarbons (PAHs), a polychlorinated biphenyl mixture (Aroclor 1254), hexachlorobutadiene (HCBD), and 7,12-dimethylbenz(a)anthracene (DMBA). Two trials were conducted. In trial l, the percent cumulative mortality of juvenile chinook salmon exposed to V. anguillarum after receiving either CHWSE, HCBD, or the mode...

Cumulative Effects of Natural and Anthropogenic Stress on Immune Function and Disease Resistance in Juvenile Chinook Salmon

Abstract Previous studies have shown that juvenile chinook salmon Oncorhynchus tshawytscha exposed in the field or the laboratory to polychlorinated biphenyls (PCBs), an anthropogenic stressor, are immunosuppressed. It is not known whether simultaneous exposure to natural stressors can increase this immunosuppression. To examine the effects of natural and anthropogenic stressors on immune function, we infected juvenile chinook salmon with metacercariae of the trematode Nanophyetus salmincola by exposing the fish to infected freshwater snails Juga plicifera. Infected (>300 metacercariae per fish) and noninfected salmon were then injected with either the commercial PCB mixture Aroclor 1254 or an acetone–emulphor carrier. B cell function was examined by in vitro hemolytic plaque-forming cell (PFC) assay. Nanophyetus salmincola infection resulted in significantly lower anterior kidney primary PFCs and lower splenic secondary PFCs. The combination of N. salmincola infection and Aroclor 1254 exposure caused a l...

Effects of Gastric and Surgical Insertions of Dummy Ultrasonic Transmitters on Juvenile Chinook Salmon in Seawater

Abstract The objective of this study was to develop guidance for tagging methods for juvenile Chinook salmon Oncorhynchus tshawytscha in their first ocean year by evaluating the effects of tagging during this critical life stage. We compared survival over 42 d among juvenile hatchery Chinook salmon receiving surgically implanted dummy ultrasonic transmitters (equivalent to VEMCO V7-1 L tags) ranging from 2.6% to 8.8% of body mass with that of fish receiving gastrically implanted tags. Survival was significantly lower in fish receiving gastrically implanted transmitters (21%) than for the gastric-sham (66%), surgery (61%), surgery-sham (58%), and control treatments (90%). Survival was also significantly higher in the control treatment than in all other treatments. The results of this study indicate that surgical insertion into the peritoneal cavity is the preferred method of transmitter implantation in juvenile Chinook salmon in their first ocean year and that the transmitters should be less than 5.8% of t...

Movements of Yearling Chinook Salmon during the First Summer in Marine Waters of Hood Canal, Washington

Abstract Migration is a fundamental component of the life history and ecology of many species, but the extent and duration of specific migrations can vary depending on species and environment. Chinook salmon Oncorhynchus tshawytscha are characterized by a spectrum of life history types with different migration patterns and spatial distributions. The objective of this study was to quantify the movements of yearling Chinook salmon smolts during their initial summer in Hood Canal, a long, narrow fjord in western Puget Sound, Washington. Fifty-eight yearling hatchery-reared smolts were tagged with acoustic transmitters and tracked during May–August 2008 with a network of 50 receivers placed throughout Hood Canal. A total of 41 fish were detected during the study period; of these, 18 fish were still being detected in Hood Canal after 100 d. Fish initially congregated near the release site and gradually dispersed during summer; individual movement rates ranged between 0.44 and 1.52 body lengths/s. Fish movement...

Partial Migration and Diel Movement Patterns in Puget Sound Coho Salmon

Abstract Partial migration, a term referring to populations in which only a fraction of the individuals migrate, is a widespread phenomenon among fishes. However, it is not always clear whether there are only two alternatives (migration or residency) or a continuum of movement patterns. For example, Coho Salmon Oncorhynchus kisutch are anadromous, and most individuals rear over the continental shelf or in offshore waters of the North Pacific Ocean; however, some Coho Salmon (known as residents) spend all or part of their marine lives within Puget Sound. The movements of residents are poorly documented, and it is unclear whether they ever leave Puget Sound and move to the coast of Washington and to what extent they move within Puget Sound. Accordingly, the goal of this study was to investigate the patterns of movement by immature Coho Salmon in Puget Sound at a series of spatial scales. We tagged 45 resident Coho Salmon in the central basin of Puget Sound with acoustic transmitters and detected their movem...

Effects of Chemical Contaminants on Growth, Age-Structure, and Reproduction of Mytilus edulis Complex from Puget Sound, Washington

Bivalves are used as sentinel species to detect chemical contaminants in the marine environment, but biological effects on indigenous populations that result from chemical exposure are largely unknown. We assessed age–weight, length–weight relationships, age structure, and reproductive status (i.e. fecundity, egg size) of the blue mussel Mytilus edulis complex from six sites in central Puget Sound, Washington, and one site in the relatively pristine area of northern Puget Sound. Results of this study suggest that mussels from urban areas of Puget Sound exhibit a lower growth rate, altered population age-structure, and potential reproductive impairment as a result of exposure to chemical contaminants. These findings support the use of mussels as sentinel species to assess the biological effects of contaminants on invertebrate populations.

Spatially Clustered Movement Patterns and Segregation of Subadult Chinook Salmon within the Salish Sea

AbstractWhile Pacific salmon are known for their extensive marine migrations, some species display much more limited alternative patterns, including residence within interior marine waters. To more clearly define the scale of movement of these residents, we used acoustic telemetry to track subadult Chinook Salmon Oncorhynchus tshawytscha caught in and released from discrete areas of the Salish Sea. Their movements were determined from detections at fixed receivers in central Puget Sound, Admiralty Inlet, the San Juan Islands, and the Strait of Juan de Fuca. Cluster analysis of the detections indicated four groups, with much less commonality of movement than might be inferred from the proximity of the tagging locations, which were only tens of kilometers apart. For example, none of the salmon tagged in central Puget Sound were detected in the San Juan Islands and vice versa. Thus, Chinook Salmon occupying central Puget Sound and the San Juan Islands may exhibit different distributions, extents of movement,...

Characterization of Salinity and Temperature Patterns in a Large River Delta to Support Tidal Wetland Habitat Restoration

Abstract Although the Snohomish River estuary remains the second largest tidal wetland complex in Puget Sound, approximately 90% of pre-settlement habitat has been disconnected from tidal exchange. This estuary is currently the focus of the largest restoration effort in Puget Sound, with opportunity to restore tidal exchange to over 50% of pre-settlement levels. The Snohomish River also currently supports populations of all anadromous Pacific salmon species, including Endangered Species Act listed Chinook (Oncorhynchus tshawytscha), steelhead (O. mykiss), and bull trout (Salvelinus confluentus). The combination of extant anadromous Pacific salmon populations, large existing tidal wetland complexes, and large restoration potential make the Snohomish River estuary a great opportunity to benefit salmon population recovery and conservation efforts. To support restoration planning and effectiveness monitoring, we developed baseline characterizations of key physical attributes (salinity and temperature). Our results indicated that brackish (0.5–30 ppt) conditions extended farther upriver than previously described, with distributary channels downstream of the middle mainstem and lower Ebey Slough remaining brackish throughout most of the year. During extreme low flows (< 0.65 m3 s-1), salt water (> 0.5 ppt) can at times intrude throughout the distributaries and up to river kilometer 15.9 above the first bifurcation. We also observed temperatures exceeding stress thresholds for juvenile salmonids throughout the estuary from July through September, a period that overlaps with juvenile rearing. This research is timely with several large restoration projects scheduled for construction by 2020, and these baseline characterizations can be used to evaluate restoration responses, as well as to inform project prioritization and monitoring.

First Records of the Night Smelt, Spirinchus starksi, in the Salish Sea, Washington

Ten species of smelts (Osmeridae), including 1 introduced species, have been found in the eastern North Pacific (Love and others 2005). Of these 10 species, 5 have been recorded from the inland marine waters of the Salish Sea, including Puget Sound and the Straits of Juan de Fuca and Georgia (Hart 1973): Whitebait Smelt (Allosmerus elongatus), Surf Smelt (Hypomesus pretiosus), Capelin (Mallotus villosus), Longfin Smelt (Spirinchus thaleichthys), and Eulachon (Thaleichthys pacificus). Results from a study using molecular markers to distinguish smelt remains found in the stomach contents of fishes (Paquin and others 2014) indicated that a specimen collected from Discovery Bay, Washington, an embayment at the eastern terminus of the Strait of Juan de Fuca, was misidentified as S. thaleichthys in the online Barcode of Life Database (BOLD; Ratnasingham and Hebert 2007). Subsequent examination of the preserved specimen has confirmed its identity as Night Smelt (Spirinchus starksi) and constitutes a new record for this species in the Salish Sea. Since this discovery, additional specimens of S. starksi have been collected in the area for inclusion in this study. To confirm the identification of the Discovery Bay specimen, both morphological and nucleotide sequence data from S. starksi were compared with data from the closely related species S. thaleichthys. Whole specimens and tissue samples (frozen or preserved in ethanol) from 11 S. starksi and 5 S. thaleichthys were obtained from the Northwest Fisheries Science Center (NWFSC) and the University of Washington Fish Collection (UW). Specimens of S. starksi were collected from Discovery Bay, Washington (n 5 1), Green Point, Washington (n 5 5), and north of Monterey Bay off the California coast (n 5 5). Specimens of S. thaleichthys were collected from the Gulf of Alaska (n 5 1), San Juan Islands (n 5 1), and Puget Sound (n 5 3) (Table 1). DNA extractions were performed on fin clips using a QIAGEN DNeasy kit (QIAGEN, Valencia, CA) and the manufacturer’s animal tissue protocol. A 750 base-pair region of the mitochondrial genome, cytochrome c oxidase I (COI), was amplified using PCR with universal fish primer cocktail C_FishF1t1-C_FishR1t1 (Ivanova and others 2007). The COI gene region has been used as the barcode for biodiversity to distinguish among species, whether they are distantly related species such as mammals and insects, or closely related congenerics (Ward and others 2005, 2009; Holloway 2006; Ward and others 2009). Nucleotide sequence data were collected for 16 samples (including the misidentified specimen of S. starksi from Discovery Bay) in both forward and reverse directions with Big Dye chemistry using EXOSAP purified PCR products. Sequences were read using an ABI 3730 automated sequencer