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Pond-Breeding Amphibian Species Distributions In A Beaver-Modified Landscape, Acadia National Park, Mount Desert Island, Maine, Jesse Cunningham Dec 2003

Pond-Breeding Amphibian Species Distributions In A Beaver-Modified Landscape, Acadia National Park, Mount Desert Island, Maine, Jesse Cunningham

Electronic Theses and Dissertations

In order to maintain pond-breeding amphibian species richness, it is important to understand how both natural and anthropogenic disturbances affect species assemblages and individual species distributions both at the scale of individual ponds and at a larger landscape scale. The goal of this project was to investigate what characteristics of ponds and the surrounding wetland landscape were most effective in predicting pond-breeding species richness and the individual occurrence of wood frog (Rana sylvatica), bullfrog (Rana catesbeiana) and pickerel frog (Rana palustris) breeding sites in a beaver-modified landscape and how this landscape has changed over time. The wetland landscape of Acadia ...


Hydroperiod Of Wetlands And Reproduction In Wood Frogs (Rana Sylvatica) And Spotted Salamanders (Ambystoma Maculatum), Mary Beth Kolozsvary Aug 2003

Hydroperiod Of Wetlands And Reproduction In Wood Frogs (Rana Sylvatica) And Spotted Salamanders (Ambystoma Maculatum), Mary Beth Kolozsvary

Electronic Theses and Dissertations

Many amphibians rely on wetlands for reproduction and the differential distribution of amphibian species along a gradient of wetland permanence is striking, yet not absolute. Wood frogs (Rana sylvatica) and spotted salamanders (Ambystoma maculatum) are thought to rely on seasonal wetlands for greatest breeding success, but there is little documentation of their reliance on these or other habitats. In my first chapter, I studied these species in wetlands across a hydrologic gradient from seasonal wetlands of short flood duration to permanently flooded sites. My results indicate that wood frogs have greatest reproductive effort and success in seasonal wetlands of short ...


Regulation Of Vitellogenin And Other Serum Proteins By Estrogen And Xenobiotic Estrogens In Salamanders, Lisa Marie Nespoli Jan 2003

Regulation Of Vitellogenin And Other Serum Proteins By Estrogen And Xenobiotic Estrogens In Salamanders, Lisa Marie Nespoli

Electronic Theses and Dissertations

Environmental estrogens pose potential health risks to humans and wildlife by disrupting physiological and developmental processes; therefore, our laboratory has been designing in vivo bioassays on induction of the egg-yolk precursor protein vitellogenin. I have provided information on vitellogenin induction by estrogens in tiger salamanders (Ambystoma tigrinum), spotted salamanders (Ambystoma maculatum), hellbenders (Cryptobranchus alleganiensis), Morelet's crocodiles (Crocodylus moreletii), and developed vitellogenin immunoassays in these species. Salamanders were estrogen-injected; blood was collected at intervals. Estrogen exposed male salamanders of all species, produced substantial quantities of a 200-kDa protein, the approximate size of vertebrate vitellogenins. Sequencing of estrogen-induced proteins showed substantial ...