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Spatiotemporal Partitioning Of Mammalian Mesopredators In Response To Drought And Urbanization In California's Central Valley, Chad W. Moura Jan 2020

Spatiotemporal Partitioning Of Mammalian Mesopredators In Response To Drought And Urbanization In California's Central Valley, Chad W. Moura

Cal Poly Humboldt theses and projects

Mammalian mesopredators commonly associated with human dominated landscapes often exhibit generalist diets, behavioral plasticity, and relatively high reproductive rates. Because of this wide range of adaptive traits, ecologists have been speculative of what conditions may drive species to change their activity and behavior to avoid or mitigate against resource competition, intraguild predation, and human disturbance. I investigated a community of common mesopredators within the Sacramento Metropolitan Area of California’s Central Valley to address whether species are spatially and/or temporally partitioning due to a defacto apex predator, coyotes (Canis latrans), and humans alongside large landscape altering disturbances: urbanization and drought. I …


Growth Of Juvenile Red Abalone (Haliotis Rufescens) Fed Different Seaweed-Based Diets, Quinn C. Wulffson Jan 2020

Growth Of Juvenile Red Abalone (Haliotis Rufescens) Fed Different Seaweed-Based Diets, Quinn C. Wulffson

Cal Poly Humboldt theses and projects

The rise of abalone aquaculture has mitigated most of the global demand placed on wild stocks of abalone; however, the current production of abalone relies heavily on naturally harvested kelp. The continued reliance on wild kelp as a feed source further contributes to the disappearance of kelp forests throughout coastal ecosystems. This study aims to better understand how juvenile red abalone Haliotis rufescens grow and utilize nutrients from three diets: a control diet of naturally harvested bull kelp Nereocystis luetkeana, a formulated commercial diet (ABKelp®), and Pacific dulse Palmaria mollis produced using Integrated Multi-Trophic Aquaculture (IMTA). Juvenile …


Recolonization Potential For Coho Salmon (Oncorhynchus Kisutch) In Tributaries To The Klamath River After Dam Removal, Max M. Ramos Jan 2020

Recolonization Potential For Coho Salmon (Oncorhynchus Kisutch) In Tributaries To The Klamath River After Dam Removal, Max M. Ramos

Cal Poly Humboldt theses and projects

Removal of four major dams on the Klamath River is scheduled to begin in 2023, restoring access to greater than 50 km of historic mainstem habitat for coho salmon. However, mainstem habitat may not be suitable for juvenile coho salmon due to elevated water temperatures and high concentrations of infectious myxospores in the summer and fast water velocities in the winter. Small, cooler tributaries can provide essential habitat for escape from deleterious conditions in the mainstem Klamath River. I used temperature and other physical features of six tributaries to the Klamath River above Iron Gate Dam to assess their capacity …


Apparent Survival Of Snowy Plovers Varies Across Years And Between Sexes In Coastal Northern California, Justin A. Windsor Jan 2020

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 …


Spatial And Temporal Genetic Structure Of Winter-Run Steelhead (Oncorhynchus Mykiss) Returning To The Mad River, California, Steven R. Fong Jan 2020

Spatial And Temporal Genetic Structure Of Winter-Run Steelhead (Oncorhynchus Mykiss) Returning To The Mad River, California, Steven R. Fong

Cal Poly Humboldt theses and projects

Distinct populations of steelhead in the wild are in decline. The propagation of steelhead in hatcheries has been used to boost population numbers for recreational fisheries and for use in conservation. However, hatchery breeding practices of steelhead can result in changes in genetic structure. I investigated the genetic structure of winter-run steelhead (Oncorhynchus mykiss) returning to the Mad River, California, where a hatchery has been used enhance production for recreational fisheries since 1971. Genetic variability in Mad River steelhead was evaluated using 96 single nucleotide polymorphisms (SNPs) among 4203 individuals, including the Mad River and nearby locations, and …


Comparing Environmental Dna And Traditional Monitoring Approaches To Assess The Abundance Of Outmigrating Coho Salmon (Oncorhynchus Kisutch) In California Coastal Streams, Emerson Alan Kanawi Jan 2020

Comparing Environmental Dna And Traditional Monitoring Approaches To Assess The Abundance Of Outmigrating Coho Salmon (Oncorhynchus Kisutch) In California Coastal Streams, Emerson Alan Kanawi

Cal Poly Humboldt theses and projects

Environmental DNA (eDNA) has the potential to dramatically increase the information available to managers regarding species distribution and abundance. Collection of reliable survey information on fish abundance is essential to monitor population trends and restoration efforts for endangered and threatened species. In Northern California, coho salmon are a federally listed species and a focus of ongoing monitoring programs and restoration projects. I examined the feasibility of using eDNA to supplement, or replace, traditional outmigrating juvenile coho salmon monitoring approaches currently used at two existing coho salmon life-cycle monitoring stations. Over the spring of 2018 and spring of 2019, I collected …


Knemidokoptes Mites And Their Effects On The Gripping Position Of Steller’S Jay Feet, Wade M. Burris Jan 2020

Knemidokoptes Mites And Their Effects On The Gripping Position Of Steller’S Jay Feet, Wade M. Burris

Cal Poly Humboldt theses and projects

Steller’s jays (Cyanocitta stelleri) with swollen legs and feet resembling the signs of scaly leg have been commonly seen around Arcata, California, USA. These signs are thought to be caused by knemidokoptic mites, a group of parasites specialized at exploiting a range of avian hosts. I compared the gripping position in the feet of jays with variable signs of this condition as an index of their ability to perch, confirmed the presence of mites and identified them to the nearest species using genetic analysis, and compared the relatedness of the cytochrome oxidase subunit I (COI) gene between mites …


The Effect Of Shade Tree Species On Bird Communities In Central Kenyan Coffee Farms, Deven Kammerichs-Berke Jan 2020

The Effect Of Shade Tree Species On Bird Communities In Central Kenyan Coffee Farms, Deven Kammerichs-Berke

Cal Poly Humboldt theses and projects

Shade coffee has been recognized as a well-studied example of a land-sharing management strategy that both creates habitat for tropical birds while also maintaining agricultural yield. Despite the general consensus that shade coffee is more “bird-friendly” than a sun coffee monoculture, little work has been done to investigate the effects of specific shade tree species on bird diversity and their capacity to help deliver ecosystem services. Previous studies in temperate regions have demonstrated that due to shared evolutionary histories, native plant species are better at promoting native arthropod numbers, which in turn support a greater number of birds. This study …