Life Sciences Commons^™

Effects Of Depth, Distance To Shore, And Water Velocity On Organismal And Extra-Organismal Environmental Dna Concentrations In A Large River, Dylan Keel

Cal Poly Humboldt theses and projects

Environmental DNA (eDNA) is a sensitive tool for detection of aquatic species and concentrations of eDNA in water samples have been useful for estimating abundance. This study evaluated the effects of depth, distance to shore, and water velocity on the concentration of organismal and extra-organismal eDNA concentrations in the Klamath River, California (basin area ≅ 40,000 km²). At each of six river cross sections 32 water samples were collected, including surface samples and depth samples evenly distributed across the cross section, and eDNA concentrations were determined for the parasite Ceratonova shasta and Chinook salmon, Oncorhynchus tshawytscha, using …

Physiological State Determinants Of Maternal Cortisol Signaling And Its Impact On Offspring Quality And Fitness, Sydney Currier

Electronic Theses and Dissertations

Assessing the intergenerational effects of maternal stress is important for predicting how offspring will respond to changing environments. The overall aim of my thesis was to quantify the effects of maternal state on maternally derived egg cortisol and determine whether this variation in egg cortisol impacts Chinook salmon offspring performance and fitness in a sex-specific way. I quantified within-female changes in maternal energetics and reproductive metrics that I linked to egg quality and ultimately embryo survival. I found egg cortisol increases with increasing maternal plasma cortisol, and increases further as plasma cortisol levels rise with each day that eggs are …

Impacts Of Flow Releases On Invertebrate Drift And Juvenile Chinook Salmon (Oncorhynchus Tshawytscha) Diet On The Trinity River Below Lewiston Dam, Thomas R. Starkey-Owens

Cal Poly Humboldt theses and projects

Benthic macroinvertebrate (BMI) drift, species composition and abundance are specific to local hydrologic and habitat conditions, which can restrict or enhance availability to salmonids as a food resource. Currently, a knowledge gap exists on the Trinity River (northern California) in how flow releases from Lewiston Dam potentially impact BMI drift and feeding opportunities for juvenile salmonids. Samples of BMIs from drift, benthos, and diets of juvenile Chinook salmon (Oncorhynchus tshawytscha) were collected from two sites in the upper Trinity River February-April 2018, during stable flow conditions (~8 ) and two increased flow conditions peaking at ~50 . Chironomidae …

Changes In Hatchery Subsidies Of Chinook Salmon In The Salish Sea: Implications For Predators, Fisheries, And Conservation, Benjamin Nelson, Eric John Ward, Ole Shelton, Joseph H. Anderson

Salish Sea Ecosystem Conference

Historically, salmon hatcheries were designed to increase fishery production and to recover depleted native populations. As demands of human protein consumption increase and wild populations continue to decline due to anthropogenic impacts like climate change and habitat loss, hatcheries and stocking programs will be called on to provide food security and to supplement threatened populations. Since 1950 over 3.7 billion Chinook salmon have been released into the Salish Sea and its tributaries in Washington State and southern British Columbia. However, relatively little research has been conducted that considers the impact of hatchery subsidies on estuarine and nearshore marine ecosystems in …

High-Resolution Archival Tags Provide New Insights Into The Underwater Foraging And Echolocation Behavior Of Resident Killer Whales Capturing Pacific Salmon, Brianna Wright

Salish Sea Ecosystem Conference

Dtags contain sensors for recording both high resolution animal movement and underwater sound. They provide a valuable tool for examining the foraging behavior of resident killer whales, a specialist predator that relies on echolocation to find and pursue Pacific salmon, its primary prey. We deployed Dtags on 32 northern residents off Vancouver Island, BC, and compared reconstructed whale dive paths to distributions of different salmonid prey. Foraging whales dove deeper, remained submerged longer, swam faster, increased their dive path tortuosity, and rolled their bodies more than during other activities. Foraging dive structure also reflected the deeper vertical distribution of Chinook …

Evaluating Common Trends In Chinook Density And The Influence Of Temperature And Salinity Patterns Among Distributary Channels In A Large River Estuary To Aid Evaluation, Planning, And Prioritization Of Restoration Activities, Joshua Chamberlin, Jason E. Hall, Todd Zackey, Frank Leonetti, Michael Rustay

Salish Sea Ecosystem Conference

Landscape context is critical in estuary restoration planning and assessment due to the complexity and size of estuaries, and the unique attributes and cumulative effects of individual restoration projects. In addition, the diversity and mobility of estuarine species, in particular juvenile salmon, highlights the importance of landscape position given certain locations in the delta are less accessible to salmon. The Snohomish River delta has been the focus of major estuary restoration efforts in recent years and efforts could result in the largest cumulative estuary restoration action in Puget Sound. While several large projects have been initiated/competed in recent years, information …

Density-Dependent And Landscape Effects Upon Estuary Rearing In Chinook Salmon: Insights From Long-Term Monitoring In Four Puget Sound Estuaries, Correigh M. Greene, Eric M. Beamer, Rich Henderson, Joshua Chamberlin, Jason Hall, Joseph H. Anderson, Matthew Pouley, Melanie Davis, Sayre Hodgson, Christopher Ellings

Salish Sea Ecosystem Conference

Juvenile Chinook salmon are well known for utilizing estuarine habitats within the tidal delta for rearing during outmigration. Several studies have linked population responses to availability of estuary habitat, and support the hypothesis that estuarine habitats are vital rearing areas for juvenile Chinook salmon. However, these coarse-scale studies provide little insight on how specific estuarine habitats contribute to rearing potential for salmon. We integrate long-term monitoring data from four estuaries of Puget Sound (Nooksack, Skagit, Snohomish, and Nisqually) to examine whether 1) Chinook populations in these rivers are limited by restricted estuary habitat, 2) hatchery releases can influence density dependent …

Southern Resident Killer Whales: From Captivity To Conservation, Colleen Weiler, Rob Lott, Erich Hoyt, Deborah Giles, Howard Garrett, Susan Berta, Rein Attemann, Giulia Good-Stefani, Francine Kershaw

Salish Sea Ecosystem Conference

The endangered Southern Resident killer whale (Orcinus orca) (SRKW) population remains the only killer whale population listed under the United States Endangered Species Act in U.S. waters since it was listed in 2005. In the 1960s and 70s, the population was reduced by approximately 40% following intensive efforts to capture individuals for a growing marine park captivity industry. The first Northwest killer whale census (1974) found just 70 remaining individuals in the SRKW community. This population has struggled to return to pre-capture numbers, and in the face of new threats including prey depletion, toxic contamination, and vessel effects, fewer than …

The Ecosystem Approach: Recovering Rivers To Help Save The Southern Resident Killer Whales, Colleen Weiler, Deborah Giles, Regina Asmutis-Silvia

Salish Sea Ecosystem Conference

The “ecosystem approach” to managing habitats is of growing interest in the world of conservation biology, with the realization that recovery of protected species ultimately relies on the health of their environment. In the case of the critically endangered Southern Resident Killer Whale (SRKW) population, prey depletion is a major threat to their survival. Research has shown that the SRKWs are highly dependent on Chinook salmon; thus the restoration of Chinook throughout the U.S. and Canada Pacific region is crucial for SRKW recovery. The significant decline of salmon abundance can be attributed to habitat loss and degradation throughout their range. …

Reproductive Characteristics Of Landlocked Fall Chinook Salmon From Lake Oahe, South Dakota, Kelsen L. Young, Michael E. Barnes, Jeremy L. Kientz

The Prairie Naturalist

Lake Oahe, South Dakota, USA, landlocked fall Chinook salmon (Oncorhynchus tshawytscha) reproductive characteristics were examined over a 27 year period, from 1988 to 2015. Mean total lengths of spawning females ranged from 665 mm (1995) to 812 mm (2015) with considerable year-to-year variation. Post-spawn female weights varied, ranging from 2.02 kg (2000) to 5.55 kg (2015), with an overall mean of 3.04 kg. Fecundity peaked at 4,555 eggs per female in 2003, which was just 3 years after a low of 2,011 eggs per female in 2000. Relative fecundity based on female weight was greatest at 1,211 eggs/kg …

Conservation Genetics On The Frontline, Kenneth W. Rand

Graduate Student Theses, Dissertations, & Professional Papers

Conservation genetics stands out as an effective tool for discovering and monitoring rare, endangered or invasive populations of plants and animals. Particularly when compared to traditional search and capture methods, it provides more holistic studies to preserve the disappearing biodiversity of the American West and the world.

Three stories highlight the work done to preserve biodiversity through the use of conservation genetics:

1. Trout Rescue: A new hope for westslope cutthroat in Montana How to save a disappearing westslope cutthroat trout through genetic rescue by adding genetic diversity to ensuring future survival in increasingly warming waters more harm than good. …

Fish Out Of Salt Water: Smoltification In Subyearling Chinook Salmon From The Laurentian Great Lakes, Steve Sharron

Electronic Thesis and Dissertation Repository

The timing of smoltification in juvenile anadromous salmonids is important to ensure individuals match their preparedness with their migration timing and the optimal conditions in the environment. I performed the first study of smoltification in adfluvial juvenile Chinook salmon naturalized in the Laurentian Great Lakes. In a hatchery study, I found that juveniles from one of these populations have similar patterns of smoltification timing to individuals from anadromous populations. Their Na⁺/K⁺ ATPase activity, a common indicator or smolt status, peaked at 7.7 μmoles ADP/mg protein/hour on July 1 in freshwater. During the peak period, individual body size …

Distribution Of Chinook Salmon (Oncorhynchus Tshawytscha) In Upper-Columbia River Sub-Basins From Environmental Dna Analysis, Matthew Benjamin Laramie

Boise State University Theses and Dissertations

Determining accurate species distribution is crucial to conservation and management strategies for imperiled species, but challenging for small populations that are approaching extinction or being reestablished. We evaluated the efficacy of environmental DNA (eDNA) analysis for improving detection and thus known distribution of Chinook salmon in the Methow and Okanogan Sub-basins of the Upper-Columbia River, Washington, USA. We developed an assay to target a 90 base pair sequence of Chinook DNA and used quantitative polymerase chain reaction (qPCR) to quantify the amount of Chinook eDNA in 1-L water samples collected at 48 sites in the sub-basins. We collected samples once …

Introduced Chinook Salmon (Oncorhynchus Tshawytscha) In Lake Huron: Do They Spawn At The Right Time?, Meghan T. Gerson

Electronic Thesis and Dissertation Repository

Chinook salmon (Oncorhynchus tshawytscha), following their introduction to the Great Lakes, have successfully colonized many tributaries. Under the hypothesis that colonization success is facilitated by intrinsic factors (i.e., preadaptation), I predicted that patterns of reproductive timing in an introduced population would show similarities with those in their native range. To test this prediction, attributes of reproductive timing were characterized in Chinook salmon from the Sydenham River, Ontario. In their native range, female Chinook salmon exhibit a seasonal decline in reproductive lifespan, a decline in fat stores, low egg retention at death (< 0.5%), and spawning at temperatures below 12.8°C. In contrast, Sydenham River Chinook salmon showed no seasonal decline in reproductive lifespan or fat stores and nineteen of twenty females had egg retention greater or equal to 0.5%. Also, many individuals (30%) spawned when water temperatures exceeded 12.8°C. Thus, individuals do not appear to be pre-adapted in this system.