Life Sciences Commons^™

Stress Ecology Of The Pacific Rattlesnakes (Crotalus Oreganus And Crotalus Helleri), Natalie Claunch

Master's Theses

Stress is a physiological state induced by disturbance or adverse environmental conditions and is modulated by the glucocorticoid hormone corticosterone (CORT) in reptiles. Stressors can have various impacts on vertebrate trait expression and may affect survival or reproduction. Little is known about the effects of chronically elevated CORT in free-ranging reptiles, or the effect of disturbance stress on venom composition in captive snakes.

In chapter 1, we investigated the effects of researcher induced disturbance on CORT levels and venom composition in a group of captive Northern Pacific rattlesnakes (Crotalus oreganus). Venom protein concentration and plasma CORT levels were …

Gender Differences In Space-Use Patterns And Microhabitat Characteristics Of Southern Flying Squirrel (Glaucomys Volans) In Northeastern Iowa, Elizabeth G. Bainbridge

Master's Theses

Southern flying squirrel (Glaucomys volans) is common throughout the eastern deciduous forests of the United States, southern Canada, Mexico, and Central America. However, within the state of Iowa G. volans currently is listed as a “species of special concern.” This status is due to general loss of local habitat and lack of information about the species within the state. The state of Iowa has lost a majority of its native land cover over the past century due to intensive agricultural practices. Most native forests have been reduced drastically. The majority of habitat that would be suitable for southern flying squirrel …

Organismal Composition And Photosynthetic Traits Of Biological Soil Crusts In Prairie Ecosystems Ofthe Great Plains, Brendon C. Mccampbell

Master's Theses

Biological soil crusts (BSCs) are soil-surface microecosystems composed of a close association of algae, cyanobacteria, fungi, lichens, and non-vascular plants with soil particles. BSCs have several ecological functions including carbon fixation, nitrogen fixation, nutrient relations, soil stabilization, water relations, and floral community development, which make them extremely important in many of the ecosystems where they occur. While BSCs have been studied throughout the American West, little work has been done in the Great Plains region where they are less prominent among the dominant vascular plant communities. This study examined organismal composition and photosynthetic traits of BSCs in four ecosystems within …