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Full-Text Articles in Life Sciences
Survival And Growth Of Juvenile Coho Salmon (Oncorhynchus Kisutch) In Restored Wetlands Of Humboldt Bay, California, Josh D. Cahill
Survival And Growth Of Juvenile Coho Salmon (Oncorhynchus Kisutch) In Restored Wetlands Of Humboldt Bay, California, Josh D. Cahill
Cal Poly Humboldt theses and projects
Substantial investment in habitat restoration efforts have been made to promote coho salmon (Oncorhynchus kisutch) recovery, yet sampling efforts to document the response of coho salmon populations to wetland restoration are limited. I investigated two cohorts of juvenile coho salmon growth, movement, and survival within the Humboldt Bay drainage in California. My study sites included restoration features and other sample areas in upland creek habitat and in lowland estuarine wetlands that were located in the four largest watersheds within the Humboldt Bay drainage. The objectives of this study were to: (1) determine if coho salmon are using restored, …
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 Large Wood Restoration On Coho Salmon In A Northern California Watershed: A Before-After-Control-Impact Experiment, Natalie B. Okun
Effects Of Large Wood Restoration On Coho Salmon In A Northern California Watershed: A Before-After-Control-Impact Experiment, Natalie B. Okun
Cal Poly Humboldt theses and projects
Substantial time, money, and effort are invested in river and stream restoration projects to aid in the recovery of imperiled salmonid populations, but there is little evidence that these efforts have had lasting positive impacts on juvenile fish growth and survival. To assess the effectiveness of large woody debris (LWD) restoration, which is one of the most common restoration practices, I evaluated the growth and survival response of endangered Central California Coast coho salmon (Oncorhynchus kisutch) in a paired watershed before-after impact-control (BACI) study. To determine if LWD supplementation influenced coho salmon growth and survival, two neighboring, similar …
Estimates Of Calf Survival And Factors Influencing Roosevelt Elk Mortality In Northwestern California, Erin Nigon
Estimates Of Calf Survival And Factors Influencing Roosevelt Elk Mortality In Northwestern California, Erin Nigon
Cal Poly Humboldt theses and projects
Survival of juvenile ungulates is known to be highly variable, yet it is fundamental to understanding the dynamics and trends of wildlife populations. Factors influencing calf survival are poorly understood in northwestern California where Roosevelt elk (Cervus canadensis roosevelti) are known to exist. The objectives of this study were 1) to estimate summer and annual survival rates and determine recruitment rates for Roosevelt elk calves in the area, 2) to evaluate differences in calf survival by examining the effects of individual and population level covariates on summer and annual calf survival, 3) to identify factors influencing the timing …
Apparent Survival Of Snowy Plovers Varies Across Years And Between Sexes In Coastal Northern California, Justin A. Windsor
Apparent Survival Of Snowy Plovers Varies Across Years And Between Sexes In Coastal Northern California, Justin A. Windsor
Cal Poly Humboldt theses and projects
Adult survival is one of the most influential vital rates affecting population growth of iteroparous organisms. Survival often varies annually due to environmental stochasticity. However, drastic variations in annual adult survival rates can have overwhelmingly negative impacts on population viability and growth. In many wild avian populations, adult survival varies between sexes and may owe to unequal risks associated with reproductive roles or predation; this is particularly true among shorebirds. I used mark-resight data from a 19-year study of Western Snowy Plovers (Charadrius nivosus nivosus) in coastal northern California to investigate sex-specific apparent survival of the adult population …
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, …
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 …
The Influence Of Canopy Cover And Climate On Early Life-Stage Vital Rates For Northern Red-Legged Frogs (Rana Aurora), And The Implications For Population Growth Rates, Kecly Mcharry
Cal Poly Humboldt theses and projects
Many amphibian species are in decline due to habitat loss and changing climates. Understanding how habitat characteristics and climate influence vital rates, and if they act in concert or in opposition can inform management decisions. This study investigated the potential interaction of canopy cover and climate on early stage vital rates of northern red-legged frogs. Demographic data were collected from sample populations in experimental canopy cover treatments across a latitudinal distribution. Rearing cages were used to estimate hatch success, and mark-recapture surveys to estimate tadpole survival. Ambient air temperature was used as an index of climate because it is easily …