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Characterizing The Habitat Use Of Pacific Coast Feeding Group Gray Whales (Eschrichtius Robustus) And The Spatial And Temporal Variability Of Their Benthic And Planktonic Invertebrate Prey In Northern California, Robyn E. Norman Jan 2024

Characterizing The Habitat Use Of Pacific Coast Feeding Group Gray Whales (Eschrichtius Robustus) And The Spatial And Temporal Variability Of Their Benthic And Planktonic Invertebrate Prey In Northern California, Robyn E. Norman

Cal Poly Humboldt theses and projects

As opportunistic foragers, the Eastern North Pacific population (~20,000) of gray whales (Eschrichtius robustus) feed on diverse benthic and planktonic invertebrates in northern Alaska foraging grounds before they undertake one of the largest yearly migrations of any mammal to breed in Baja California, Mexico. While most of the population travels to the summer foraging grounds in Alaska, a sub-group of whales (~230) called the Pacific Coast Feeding Group (PCFG) summer between British Columbia, Canada, and northern California. The diet of PCFG whales typically includes high-density and/or high-caloric prey items like mysids and diverse species of amphipods, yet a …


Overwinter Ecology Of Rusty Blackbirds (Euphagus Carolinus) In Arkansas, Araks Ohanyan Apr 2021

Overwinter Ecology Of Rusty Blackbirds (Euphagus Carolinus) In Arkansas, Araks Ohanyan

ATU Theses and Dissertations 2021 - Present

Rusty Blackbirds are one of the most rapidly declining songbirds in North America. They have lost an estimated 85-95% of their population since the 1960s. Unfortunately, we currently do not know what is causing their decline. However, since habitat alteration and loss in their nonbreeding range has been much more severe than in their breeding range, many think the decline is associated with winter habitat loss. Consequently, knowledge of winter ecology, with a focus on habitat use and selection, may provide management insights useful for reversing the decline. My field assistants and I (hereafter we) used radio telemetry to collect …


Using Acoustic Telemetry To Analyze The Impacts Of Common Carp On Wild Rice Restoration, Franklin Zomer Mar 2021

Using Acoustic Telemetry To Analyze The Impacts Of Common Carp On Wild Rice Restoration, Franklin Zomer

All NMU Master's Theses

Wild rice (Zizania palustris) is an important cultural, spiritual, and dietary resource to Lake Superior Ojibwe. Common Carp (Cyprinus carpio) are an introduced species that negatively impact aquatic vegetation through changes in water quality, uprooting of plants, and consumption of seed. Acoustic telemetry was used to document Common Carp movements in Waishkey Bay in the upper St. Marys River, MI where wild rice habitat is present. Exclosures were established to measure the influence of carp presence on wild rice seeding success. Common Carp were observed to spend much of their time in Waishkey Bay but also …


Seasonal Variation In Home-Range And Core-Area Size In Verreaux's Sifaka, Brynn Harshbarger Jan 2021

Seasonal Variation In Home-Range And Core-Area Size In Verreaux's Sifaka, Brynn Harshbarger

Theses, Dissertations and Capstones

Primates living in seasonal forests must adapt to extreme fluctuation in resource availability. Verreaux’s sifaka ( ) live in Madagascar’s highly seasonal tropical dry forests and experience periods of extreme resource abundance and scarcity. Home- range and core-area size were measured using 95% and 50% kernel estimation, and 95% minimum convex polygons to compare seasonal shifts in space use based on resource availability. There have been no long-term space use studies on Verreaux’s sifaka; therefore, we do not know how their space use changes over time in an environment which is both highly seasonal and highly variable. Our study leverages …


Ecological And Social Drivers Of Mexican Gray Wolf (Canis Lupus Baileyi) Home Range Patterns Across Spatiotemporal Scales, Evelyn M. Lichwa Jan 2021

Ecological And Social Drivers Of Mexican Gray Wolf (Canis Lupus Baileyi) Home Range Patterns Across Spatiotemporal Scales, Evelyn M. Lichwa

Cal Poly Humboldt theses and projects

Elucidating factors influencing home range size are fundamental relationships that can be described for any wildlife species, particularly those of conservation concern. The Mexican gray wolf (Canis lupus baileyi) is an endangered sub-species of the gray wolf whose home range patterns have not yet been studied. I estimated home range sizes for 22 Mexican wolf packs using Brownian Bridge Movement Models (95% UD). Generalized linear mixed effect models were used to evaluate environmental and social variables across four timeframes. Annual home range size was inversely related to human density and tree cover. During the denning period, home range …


Comparative Spatial And Behavioral Ecology Of The Prairie Lizard Sceloporus Consobrinus In The Arkansas River Valley, E. A. Free Kashon Aug 2020

Comparative Spatial And Behavioral Ecology Of The Prairie Lizard Sceloporus Consobrinus In The Arkansas River Valley, E. A. Free Kashon

Theses and Dissertations from 2020

Habitat-driven differences in reptile life-histories have been observed in many species. Prairie lizards, Sceloporus consobrinus, in the Arkansas River Valley inhabit rocky, forested, and intermediate habitat types that exhibit different thermal resource availabilities and habitat structures. I studied prairie lizard space usage and antipredator responses to examine whether lizards exhibit habitat-driven differences in ecology, and whether these differences are influenced, in part, by individual personality. I utilized radio telemetry to track lizards in each of these habitat types and established estimates of space usage and daily linear movements. I used behavioral approaches to quantify lizard antipredator responses to a simulated …


Effects Of Energy Development On Movements, Home Ranges, And Resource Selection Of White-Tailed Deer In The Western Dakotas, Bailey S. Gullikson Jan 2019

Effects Of Energy Development On Movements, Home Ranges, And Resource Selection Of White-Tailed Deer In The Western Dakotas, Bailey S. Gullikson

Electronic Theses and Dissertations

Oil and natural gas development has increased in recent years and research is needed to assess potential impacts on white-tailed deer (Odocoileus virginianus) populations. Our objectives were to document movements, home ranges, and resource selection of female white-tailed deer in response to energy development in the western Dakotas. Our study areas included Dunn County, North Dakota, an area with current oil and gas development, and Grant County, North Dakota, and Perkins County, South Dakota, areas without current oil and gas development. We captured and fitted 150 female deer with Very High Frequency (VHF) collars across study sites, and …


Factors Influencing Parental Care And Home Range Size Of A Monomorphic Species, The Red-Headed Woodpecker (Melanerpes Erythrocephalus), L. Abigail Walter Jan 2019

Factors Influencing Parental Care And Home Range Size Of A Monomorphic Species, The Red-Headed Woodpecker (Melanerpes Erythrocephalus), L. Abigail Walter

Theses and Dissertations

Parental care in animals can be costly and is shared between both parents in many bird species. Not surprisingly, most studies of how parental care is shared between the sexes are in sexually dimorphic species, and much less in known about sexually monomorphic species where sex cannot be determined in the field. This has prevented a full understanding of parental care behaviors – which are intrinsically linked to fitness – in species such as the Red-headed Woodpecker (Melanerpes erythrocephalus) that is experiencing population declines throughout much of its range. In this study we assessed whether Redheaded Woodpecker brooding time, nestling …


Diet And Space Use Of The Martial Eagle (Polemaetus Bellicosus) In The Maasai Mara Region Of Kenya, Richard Stratton Hatfield Jan 2018

Diet And Space Use Of The Martial Eagle (Polemaetus Bellicosus) In The Maasai Mara Region Of Kenya, Richard Stratton Hatfield

Theses and Dissertations--Forestry and Natural Resources

The martial eagle (Polemaetus bellicosus) is a vulnerable species that is declining throughout large portions of its range. There is an urgent need to improve understanding of this species’ ecology to inform its conservation. I equipped 20 adult martial eagles with global positioning system backpack transmitters to characterize diet and space use of the species in the Maasai Mara region of Kenya. The resulting high-resolution transmitter data sets allowed for the rapid location of kills and provided a means to estimate home range size. From November 2016 to April 2018, 191 kills were identified from 206 kill location …


The Spatial Ecology And Microhabitat Selection Of The Pygmy Rattlesnake (Sistrurus Miliarius) In Southwestern Missouri, Dylan Wallace Maag Dec 2017

The Spatial Ecology And Microhabitat Selection Of The Pygmy Rattlesnake (Sistrurus Miliarius) In Southwestern Missouri, Dylan Wallace Maag

MSU Graduate Theses

Despite a wide distribution throughout the southeastern United States, pygmy rattlesnakes (Sistrurus miliarius) have received less research attention than many other rattlesnake species. I captured a total of 33 S. miliarius at the Drury-Mincy Conservation Area (DMCA) and retained 14 large individuals (mostly gravid females) for a radio telemetry study. Snakes were primarily captured during evening road driving surveys and were encountered rarely with any other sampling technique. Sistrurus miliarius are widespread at DMCA where they were encountered in forest, savanna, and glade habitats. Snakes selected microhabitats with more vegetative cover and tree canopy closure than random sites …


Seasonal Habitat Selection Of The North American Porcupine (Erethizon Dorsatum) In A Coastal Dune Forest, Cara L. Appel Jan 2016

Seasonal Habitat Selection Of The North American Porcupine (Erethizon Dorsatum) In A Coastal Dune Forest, Cara L. Appel

Cal Poly Humboldt theses and projects

Wildlife-habitat relationship studies are important for understanding the factors that determine where species occur in space and time. Habitat selection by generalist species should be studied on fine spatial and temporal scales to avoid masking important differences between seasons, localities, or orders of selection. I conducted the first study of habitat use and general ecology of North American porcupines (Erethizon dorsatum) in a coastal dune environment. Specifically, I assessed changes in body mass, home range size, and habitat selection in relation to the potential for seasonal nutritional and survival bottlenecks as reported elsewhere. Although they are considered generalists, …


Ecology And Flock-Following Behavior Of The Wedge-Billed Woodcreeper In Eastern Ecuador, Abigail Darrah May 2013

Ecology And Flock-Following Behavior Of The Wedge-Billed Woodcreeper In Eastern Ecuador, Abigail Darrah

Graduate Theses and Dissertations

The wedge-billed woodcreeper (Glyphorynchus spirurus) is a common understory suboscine passerine of lowland Neotropical rainforests. It frequently joins mixed-species understory flocks but also regularly forages alone, and thus is an excellent model species on which to conduct comparative behavioral observations to examine the hypothesized costs and benefits of flock-following. Individuals exhibit variable flocking propensities (proportion of time spent with flocks), and thus observing the correlations between flocking propensity and physical and environmental factors can provide further insight into the importance of flock-following to the ecology of this species. Despite its abundance at many sites and its wide geographic range, surprisingly …


Examining Habitat Selection And Home Range Behavior At Multiple Scales In A Population Of Eastern Box Turtles, (Terrapene C. Carolina), With Notes On Demographic Changes After 17 Years, Brian Anthony Williamson Jan 2013

Examining Habitat Selection And Home Range Behavior At Multiple Scales In A Population Of Eastern Box Turtles, (Terrapene C. Carolina), With Notes On Demographic Changes After 17 Years, Brian Anthony Williamson

Theses, Dissertations and Capstones

The Eastern Box Turtle, Terrapene c. carolina, is a terrestrial species native to the eastern United States. Once considered common, it is currently declining in much of its range due to habitat destruction and disease. To conserve the species, knowledge of Eastern Box Turtle habitat selection and the factors influencing their movement is necessary. Although the home range behavior of the Eastern Box Turtle has been well studied, few studies have quantified habitat selection at the home-range scale. Therefore, I examined home-range selection and within home range habitat selection in a population of Eastern Box Turtles at Hungry Beech Nature …


Wintering White-Throated Sparrows (Zonotrichia Albicollis): Home Ranges, Aggression And Corticosterone, Marissa Ann Buschow Jan 2013

Wintering White-Throated Sparrows (Zonotrichia Albicollis): Home Ranges, Aggression And Corticosterone, Marissa Ann Buschow

Online Theses and Dissertations

White-throated sparrows (Zonotrichia albicollis) are songbirds that spend the non-breeding season in southeastern North America, where they form philopatric territorial flocks. Flocks exhibit dominance hierarchies, with dominance rank associated with an individual's age and prior residence in the territory. Although social behaviors within flocks are well studied, few studies have described winter home ranges. I tagged white-throated sparrows (n = 12) in Madison County, Kentucky, with 0.9-g radio transmitters during the winter of 2010-2011. Locations were entered into ArcGIS and home range sizes were estimated with 50% and 95% kernel analysis for individuals with at least five locations. Mean core …


Cougar Resource Selection In Two Mountain Ranges In Utah: A Study On Scale And Behavior, Wendy R. Rieth May 2010

Cougar Resource Selection In Two Mountain Ranges In Utah: A Study On Scale And Behavior, Wendy R. Rieth

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An understanding of habitat relationships is essential for managing hunted species, such as cougar, that are difficult to census. In the first phase of this study, I used aerial telemetry data to examine diurnal cougar resource selection at 2 scales, and compared results between 2 study sites, the Oquirrh Mountains and Monroe Mountain, Utah. In the second phase of this study, I used conditional logistic regression models and GPS collar data from the Oquirrh Mountains to determine whether cougar resource selection varied over 3 behaviors (prey caching, resting at a daybed site, and nocturnal activities) and 2 scales.

Results from …


Seasonal Home Range Sizes, Transboundary Movements And Conservation Of Elephants In Northern Tanzania, Alfred P. Kikoti Sep 2009

Seasonal Home Range Sizes, Transboundary Movements And Conservation Of Elephants In Northern Tanzania, Alfred P. Kikoti

Open Access Dissertations

Although the unprotected lands of northern Tanzania support large numbers of elephants, and provide critical linkages for wildlife movements across the region, there is little information on the dispersal patterns of elephants in these unprotected lands. Our home range measures (100% MCP) of 21 elephants with satellite collars in four study regions were highly variable (191 to 3,698 km2). Home range sizes (95% fixed kernel) of bulls were typically larger than those of females, and wet season ranges were typically larger than dry season ranges. There were large differences in average home range sizes reflected varying strategies for obtaining food …


Spatial Ecology, Population Structure, And Conservation Of The Wood Turtle, Glyptemys Insculpta, In Central New England, Michael T. Jones May 2009

Spatial Ecology, Population Structure, And Conservation Of The Wood Turtle, Glyptemys Insculpta, In Central New England, Michael T. Jones

Open Access Dissertations

Abstract (Summary) Wood turtles ( Glyptemys insculpta ) are of conservation interest rangewide. Anecdotal accounts demonstrate that some populations have been decimated since 1850, and recent studies demonstrate that declines are still underway. From 2004-2008 I investigated the ecology of wood turtles in Massachusetts and New Hampshire. I obtained between one and five years of annual home range data for 150 turtles, and evaluated population structure at 31 sites in five major watersheds. Seasonal floods displaced 7% of wood turtles annually in one watershed, and accounted for elevated mortality. Twelve wood turtles were displaced < 16.8 km, and two were displaced over a 65-foot dam. Several turtles overwintered at their displacement site and two returned successfully, indicating that floods are a mechanism of population connectivity. Several homing turtles ended up in new areas. Turtles occupied stream segments with gradient < 1%, lower than generally available. Agricultural machinery accounted for most observed mortality, followed by automobiles and mammals. Female turtles exhibit smaller home ranges in agricultural areas. Older turtles move farther from the river than do young turtles, possibly reflecting their familiarity with a former landscape. Population density ranged from 0-40.4 turtles/river-kilometer. The highest densities occur in central New Hampshire and lower densities occur in the Housatonic watershed. Population density is negatively correlated with agriculture at both riparian and watershed scales, and responds unimodally to forest cover. Wood turtle populations in western Massachusetts are declining by 6.6-11.2% annually. I estimated ages of turtles by assessing shell-wear rates from photographs. Wood turtles regularly achieve ages over 80 years, and like related species, do not exhibit clear signs of senescence. Old wood turtles are reproductively dominant, and their survival rates are twice as high as young turtles. Carapace scutes appear to require 80 years to become worn. Population modeling indicates that wood turtle populations are declining in New England due to anthropogenic and natural factors. Conservation efforts must address the effects of agriculture on adult survival. Climate change may negatively affect northeastern wood turtles through increased flooding. Populations in mountainous areas may be likely candidates for conservation because they don't occupy prime agricultural land, but may be more susceptible to floods.