Dissertation
CLIMATE CHANGE AND ECOLOGICAL MODELS OF AMPHIBIAN COMMUNITIES IN PALOUSE PRAIRIE WETLANDS
Doctor of Philosophy (PhD), Washington State University
01/2020
Handle:
https://hdl.handle.net/2376/112271
Abstract
Most wetlands in Palouse Prairie have been lost due to intensive agricultural development and amphibians now occupy a transformed landscape dominated by human use. I used machine learning statistical techniques to evaluate the performance of 30 environmental variables to predict the occurrence of 7 species of amphibians in 99 wetlands in Palouse Prairie and the Columbia River Basin of central Washington. Algorithmic models generally used about 3-5 ecological, landscape, or spatial variables to correctly predict amphibian occupancy in wetlands with high accuracy. These models demonstrate the adverse effects of non-native fish on pond-breeding amphibians and the importance of different wetland hydroperiods and ecological settings to influence amphibian breeding and conservation in novel human-dominated ecosystems.Ephemeral wetlands are productive for many breeding amphibian species partly because they dry up seasonally and are devoid of predatory fish. However, increasing temperatures and altered precipitation patterns that accompany global climate change may threaten these ecosystems if wetlands dry before amphibians can undergo metamorphosis. I studied growth dynamics of long-toed salamanders in Palouse Prairie wetlands to evaluate the hypothesis that growth was influenced by wetland periodicity and that salamander larva would be forced to emerge at a smaller body size in seasonally-flooded wetlands. I used machine learning modeling techniques to compare sizes of salamander larvae among different wetlands across time, elevation, and spatial landscapes in Palouse Prairie and found that size distributions were smaller in ephemeral ponds that dried more quickly and larger in more permanent wetlands. Salamanders originating from ephemeral wetlands were smaller as adults than were those coming from permanent wetlands suggesting a developmental penalty or genetic differences. If climate change alters the seasonal flooding dynamics of wetlands, it may influence population dynamics and survival of amphibians in Palouse Prairie wetlands.
Metrics
79 File views/ downloads
48 Record Views
Details
- Title
- CLIMATE CHANGE AND ECOLOGICAL MODELS OF AMPHIBIAN COMMUNITIES IN PALOUSE PRAIRIE WETLANDS
- Creators
- Erim Gomez
- Contributors
- Rodney D Sayler (Advisor)Caren S Goldberg (Committee Member)Paul A Verrell (Committee Member)
- Awarding Institution
- Washington State University
- Academic Unit
- Environment, School of the (CAHNRS)
- Theses and Dissertations
- Doctor of Philosophy (PhD), Washington State University
- Number of pages
- 103
- Identifiers
- 99900581608601842
- Language
- English
- Resource Type
- Dissertation