Life Sciences Commons^™

Effects Of Coyote Removal On Pronghorn And Mule Deer Populations In Wyoming, Dylan Earl Brown

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I studied the relationship between coyote (Canis latrans) removal and pronghorn (Antilocapra americana) and mule deer (Odocoileus hemionus) density and fawn:doe ratios in southwest Wyoming and northeast Utah in 2007 and 2008. Coyote removal variables studied included the number of coyotes removed, ground hours worked, total hours worked, coyotes removed/aerial gunning hour, coyotes removed/ground work hour, and coyotes removed/total effort hour. None of the variables explained changes observed in fawn:doe ratios of pronghorn or mule deer. The number of coyotes removed, ground hours worked, total hours worked, and coyotes removed/aerial gunning hour were positively …

Livestock Mortality At Beef Farms With Chronic Wolf (Canis Lupus) Depredation In The Western Great Lakes Region (Wglr), Arion Vandergon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Gray wolf (Canis lupus) depredation on beef calves has been studied extensively in recent years. As wolf populations increase throughout the United States there is a corresponding increase in wolf/livestock interactions. Most research concentrates on summaries of reported depredations and surveys of producers affected by depredations. The objective of this study was to present data on the fate of beef calves on 3 farms in Minnesota and Wisconsin over a 2-year period. Predator presence/absence was studied as an indicator of potential depredations. Also, data are presented comparing 2 techniques that may aid researchers and livestock producers with monitoring …

Movement Patterns Of Phrynosoma Mcallii And Phrynosoma Platyrhinos In Response To Substrate Texture, Daniel H. Foley Iii

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During the summers of 1999 and 2000 the apparent habitat partitioning of two species of sympatric horned lizards was investigated at the Barry M. Goldwater Bombing Range near Yuma, Arizona. The flat-tailed horned lizard, Phrynosoma mcallii, and the desert horned lizard, P. platyrhinos, overlap in range in portions of the Sonora desert in the southwestern United States. However, upon finer scale examination, it appeared that these horned lizards were partitioning the available habitat according to soil substrate texture. Phrynosoma mcallii appeared to be exclusively found in areas of fine, loose, wind-blown sands, in contrast to P. platyrhinos, …

Human-Bear Interactions In The Backcountry Of Yosemite National Park, Bruce Charles Hastings

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objective of this study was to quantitatively document interactions between black bears and backcountry visitors, and to identify the factors affecting those encounters. Fine hundred and ninety-two interactions were observed. The most common responses of visitors to bears were to watch, walk toward, and talk to others and/or point at the bear. Bears responded to humans largely by walking away, watching, traveling around, walking toward, and running away from people.

Each behavior for both species was categorized into one of four response classes: (1) fear/avoidance, (2) neutrality, (3) approach, or (4) aggression. Over 65 percent of visitor responses were …

Reproductive Success Of The White-Faced Ibis: The Effects Of Pesticides And Colony Characteristics, Benjamin B. Steele

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Reproductive success of white-faced ibis (Plegadis chihi) was measured in nine colonies on marshes in northern Utah during 1979. The effects of pesticides and characteristics of colonies and sub-colonies on reproductive success were examined.

DDE was present in all 80 eggs sampled and had a geometric mean concentration of 1.25 ppm. Shell thickness of 176 eggs was 4.3 percent below pre-1945 thickness. Shell thickness was weakly correlated with residues of DDT, DDE, Dieldrin, and heptachlor epoxide. Residues of these four pesticides were all correlated with each other. However, because of the stronger correlations between shell thickness and two …

The Social Behavior Of Brown Bears At Mcneil River, Alaska, Allan L. Egbert

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The social behavior of brown bears (Ursus arctos) was studied during the summers of 1972 and 1973 as bears fished for salmon at McNeil River, Alaska. Study objectives were to determine behavioral characteristics of bears in relation to sex and age, changes in social behavior over a 40-day long fishing season, social and environmental parameters correlated with the occurrence of behavior, and to test the hypothesis that brown bears modify social behavior in a feeding aggregation to exploit a resource limited in time and space.

Over one-half of the agonistic interactions consisted of passive deferrals. Encounters that included …

An Analysis Of Sound Communication In The Water Vole, Microtus Richardsoni (Rodentia: Microtinae), Dane R. Tang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Adult members of the species Microtus richardsoni were used to study the importance of acoustic communication in these voles. Tests were run with single individuals and nonbreeding pairs of voles to obtain recordings and sonagraphs of sounds emitted during exploration of a new cage, agonistic encounters, encounters with a potential predator and in response to miscellaneous aversive stimuli. Of the four groups of tests conducted, sounds were used by M. richardsoni during the last three. The results of this study showed that the water vole emitted ten different call types or sounds. These sounds were separated by similarity into Group …