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Articles 1 - 8 of 8
Full-Text Articles in Aquaculture and Fisheries
Seasonal Growth, Movement, And Survival Of Juvenile Coho Salmon (Oncorhynchus Kisutch) Utilizing Restored Rearing Habitat, Monica S. Tonty
Seasonal Growth, Movement, And Survival Of Juvenile Coho Salmon (Oncorhynchus Kisutch) Utilizing Restored Rearing Habitat, Monica S. Tonty
Cal Poly Humboldt theses and projects
The Scott River supports the most robust population of threatened Coho Salmon Oncorhynchus kisutch remaining in the Klamath River basin. Even in the Scott River, low quality and restricted extent of juvenile rearing habitat limits the Coho Salmon population to a small fraction of historic abundance. To support persistence and recovery of Scott River Coho Salmon, the Scott River Watershed Council (SRWC) has constructed a portfolio of restoration projects to improve juvenile rearing habitat, including beaver dam analogs (BDAs). The Scott River BDAs were the first implemented anywhere in California. This study compares juvenile Coho Salmon responses associated with production …
Effects Of Harvest Regulations And Post-Release Hooking Mortality On Walleye Populations In South Dakota, Cade Lyon
Electronic Theses and Dissertations
Harvest regulations are commonly implemented to manipulate fisheries stocks. By regulating the size and number of fish that are harvested by anglers, managers are able to meet the goals and needs of regions. However, these management actions come with the potential for negative consequences. Overexploitation due to less restrictive harvest regulations can cause collapses in fisheries populations. In addition, indirect consequences such as hooking mortality brought on by length-based regulations can also be detrimental to populations. In this study, I investigated the effects of various harvest regulations on Walleye populations in three western South Dakota irrigation reservoirs: Angostura, Belle Fourche, …
Overwinter Survival And Movement Of Juvenile Coho Salmon (Oncorhynchus Kisutch) In Relation To Large Woody Debris And Low-Velocity Habitat In Northern California Streams, John D. Deibner-Hanson
Overwinter Survival And Movement Of Juvenile Coho Salmon (Oncorhynchus Kisutch) In Relation To Large Woody Debris And Low-Velocity Habitat In Northern California Streams, John D. Deibner-Hanson
Cal Poly Humboldt theses and projects
Some studies suggest that Coho Salmon populations are limited by overwinter survival as a result of insufficient winter habitat. While many small-scale projects aim to define reach and basin-level habitat requirements for Coho Salmon, large-scale studies that assess multiple independent populations remain few. For my research, I quantified large woody debris (LWD) by volume and low-velocity rearing habitat (LVH) as percent area in three coastal watersheds of similar size in northern California to untangle the relationships between Coho Salmon overwinter survival, emigration timing and specific winter habitats. I used mark-recapture techniques with PIT tags to formulate Cormack-Jolly-Seber models for each …
A Time- And State-Based Approach To Estimate Winter Movement And Survival Of Juvenile Coho Salmon (Oncorhynchus Kisutch) In Freshwater Creek, California, Nicholas Paul Van Vleet
A Time- And State-Based Approach To Estimate Winter Movement And Survival Of Juvenile Coho Salmon (Oncorhynchus Kisutch) In Freshwater Creek, California, Nicholas Paul Van Vleet
Cal Poly Humboldt theses and projects
Accounting for life history diversity and overwinter survival of juvenile Coho Salmon is important to inform restoration and recovery efforts for this threatened species. Multiple seaward migration patterns of Coho Salmon have been identified, including spring fry migrants, fall and winter parr migrants, and spring smolt migrants. Previous studies have indicated that spring smolt migrants have low overwinter survival rates while they are rearing in upstream habitats, suggesting that freshwater overwinter survival may be one factor that limits smolt production. However, previous research did not account for the early emigration of fall and winter parr migrants from the study area, …
Impact Of Disease On The Survival Of Three Commercially Fished Species, John M. Hoenig, Maya L. Groner, Matthew W. Smith, Wolfgang K. Vogelbein, David M. Taylor, Donald F. Landers Jr., John T. Swenarton, David T. Gauthier
Impact Of Disease On The Survival Of Three Commercially Fished Species, John M. Hoenig, Maya L. Groner, Matthew W. Smith, Wolfgang K. Vogelbein, David M. Taylor, Donald F. Landers Jr., John T. Swenarton, David T. Gauthier
Biological Sciences Faculty Publications
Recent increases in emergent infectious diseases have raised concerns about the sustainability of some marine species. The complexity and expense of studying diseases in marine systems often dictate that conservation and management decisions are made without quantitative data on population-level impacts of disease. Mark-recapture is a powerful, underutilized, tool for calculating impacts of disease on population size and structure, even in the absence of etiological information. We applied logistic regression models to mark-recapture data to obtain estimates of disease-associated mortality rates in three commercially important marine species: snow crab (Chionoecetes opilio) in Newfoundland, Canada, that experience sporadic epizootics …
Evaluation Of Parameter Estimation And Field Application Of Transgenerational Genetic Mark-Recapture, Ryan W. Whitmore
Evaluation Of Parameter Estimation And Field Application Of Transgenerational Genetic Mark-Recapture, Ryan W. Whitmore
Cal Poly Humboldt theses and projects
Use of a genetic-based analogue of the traditional mark-recapture method (transgenerational genetic mark-recapture, tGMR) is rapidly expanding as a means to estimate total escapement of Pacific salmon. The tGMR approach is similar to the simple Lincoln-Peterson mark-recapture method. In tGMR, adults returning to fresh water to spawn are collected in the first sampling occasion and their juvenile offspring that are migrating out to sea are collected during the second sampling occasion. Recaptures are determined by the number of parent-offspring pairs identified through genetic parentage analysis of the adult and juvenile collections. Two versions of tGMR are currently in use, referred …
Determining Scaphirhynchus Sturgeon Population Demographics And Dynamics: Implications For Range-Wide Management, Recovery, And Conservation, Martin J. Hamel
Determining Scaphirhynchus Sturgeon Population Demographics And Dynamics: Implications For Range-Wide Management, Recovery, And Conservation, Martin J. Hamel
School of Natural Resources: Dissertations, Theses, and Student Research
Sturgeons (Acipenseridae) have experienced world-wide declines as a result of anthropogenic effects such as over-harvest, habitat degradation, altered flow regimes, and pollution. Nearly all European and Asian sturgeon species have experienced population declines and have subsequently been classified as either threatened or endangered. North American sturgeons have experienced a similar plight in that all eight native sturgeon species are listed as endangered, threatened, or of special concern. Direct linkages between North American sturgeon declines and anthropogenic effects are difficult to assess due to scale considerations, fluctuating environmental conditions, difficulty in capture, and the interaction of all these effects. To recover, …
Estimating Predation On Declining River Herring: Tag-Recapture Study Of Striped Bass In The Connecticut River, Eric T. Schultz, Justin P. Davis, Jason Vokoun
Estimating Predation On Declining River Herring: Tag-Recapture Study Of Striped Bass In The Connecticut River, Eric T. Schultz, Justin P. Davis, Jason Vokoun
EEB Articles
Populations of anadromous alewife Alosa pseudoharengus and blueback herring Alosa aestivalis, collectively referred to as river herring, have declined in the Connecticut River. A hypothesis for why river herring have declined is that predation pressures have increased associated with recent increases in abundance of striped bass Morone saxatilis. Information on striped bass abundance, size structure, and consumption rates are required to test this hypothesis. This study was designed to provide estimates of striped bass population size in the Connecticut River during the spring migration season, via an intensive mark-recapture exercise and either an open or robust mark-recapture model. …