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Full-Text Articles in Life Sciences
A Return To The Staging Grounds: Reassessment Of Aleutian Cackling Goose Spring Distribution In North Humboldt Bay, Shaun W. Thornton
A Return To The Staging Grounds: Reassessment Of Aleutian Cackling Goose Spring Distribution In North Humboldt Bay, Shaun W. Thornton
Cal Poly Humboldt theses and projects
After a 15-year interval in research, spatial and temporal patterns of the Aleutian cackling goose during spring staging was assessed again in 2022. During my study, 3,389 goose flocks were recorded in Arcata Bottoms staging site, 1 January to 21 April 2022, amounting to an estimated total of 2,248,512 goosedays, which was 336.8% higher than 2007 estimates of 667,485 goosedays. Geese continued to use pastures with a wide range of landscape characteristics primarily represented by livestock grazing practices. Goose use was greater than availability on beef-cattle fields early in the season and dairy-cow fields later in the season. Human disturbances …
Genetic Evaluation Of The Current Distribution And Possible Diffrentations Between Lasiurus Borealis And Lasiurus Frantzii In Southwestern North America, Zeinab M. Haidar
Genetic Evaluation Of The Current Distribution And Possible Diffrentations Between Lasiurus Borealis And Lasiurus Frantzii In Southwestern North America, Zeinab M. Haidar
Cal Poly Humboldt theses and projects
Several recent accounts of overlap and historic misidentifications regarding two species of the genus Lasiurus, Western red bat (Lasiurus frantzii) and Eastern red bat (Lasiurus borealis), have cast doubt on our understanding of their distribution, assumed spatial allopatry, and interactions in the United States Southwest. With the use of morphometrics and genetic sequencing, utilizing tissue collected from specimens throughout California and adjoining states, we have reassessed the current distribution, best practices for field identification, and genetic differentiation between both species. Appropriate species classification by region was achieved utilizing mitochondrial DNA, targeting the cytochrome c oxidase …
Building Habitat Suitability Models To Examine Distribution Shifts For The Black-Headed Grosbeak, Hairy Woodpecker, And Yellow-Rumped Warbler Due To Drought, Fire, And Bark Beetle Infestation In The Pacific Northwest, Holli Nicole Pruhsmeier
Building Habitat Suitability Models To Examine Distribution Shifts For The Black-Headed Grosbeak, Hairy Woodpecker, And Yellow-Rumped Warbler Due To Drought, Fire, And Bark Beetle Infestation In The Pacific Northwest, Holli Nicole Pruhsmeier
Cal Poly Humboldt theses and projects
Spatial models that describe species distributions are valuable in determining how environmental impacts, such as drought, fire, and bark beetle infestations, have shifted these distributions and guide management decisions. In this thesis, I begin by comparing the utility of two datasets by building habitat suitability models for Black-headed Grosbeak, Hairy Woodpecker, and Yellow-rumped Warbler. By combining the datasets, I created response curves that explain habitat associations I expected from each species. I expanded upon the methods section to compare pre- and post-drought data from the 2011 California multi-year drought and evaluate how the three avian species have shifted their habitat …
Density And Distribution Of Piscivorous Fishes In The Sacramento – San Joaquin Delta, Christopher M. Loomis
Density And Distribution Of Piscivorous Fishes In The Sacramento – San Joaquin Delta, Christopher M. Loomis
Cal Poly Humboldt theses and projects
Predatory fishes, including numerous introduced species, are common to the Sacramento – San Joaquin Delta, but abundance data for most species is insufficient to determine the Delta-wide distribution and ecological impacts of these species. Predatory fishes (e.g. Striped Bass, Largemouth Bass have long been suspected of contributing to the decline of native species, including salmonids, but data has been insufficient to investigate this hypothesis. In this study, I present a novel method to assess predator fish populations across the southern Delta using DIDSON acoustic cameras and analyze the environmental associations that form the landscape and fine-scale distribution of predatory fishes. …
Changes In Demography, Distribution, And Diet In Garter Snakes Following Eradication Of A Non-Native Prey Subsidy, Justin A. Demianew Mr.
Changes In Demography, Distribution, And Diet In Garter Snakes Following Eradication Of A Non-Native Prey Subsidy, Justin A. Demianew Mr.
Cal Poly Humboldt theses and projects
Interactions between non-native and native consumers are often complex and cryptic. I shed light on relationships between non-native brook trout (Salvelinus fontinalis), native amphibians, their shared predator (aquatic garter snake; Thamnophis atratus) and a sympatric amphibian specialist (common garter snake; T. sirtalis) using a treatment-control removal experiment in a sub-alpine system of northern California. Eradication of non-native S. fontinalis resulted in an immediate decrease in T. atratus abundance and survival, whereas their abundance increased in concert with T. sirtalis in an adjacent control basin. Additionally, T. atratus body condition decreased substantially during this time, despite their …