Master of Environmental Science, Miami University, 2015, Environmental Sciences

Managing wetland habitats for migrating and native marsh bird species is a major goal of Ottawa National Wildlife Refuge. The purpose of this practicum project was to utilize statistical and GIS skills to improve the knowledge base of how wetland habitat management has been impacting the presence of focal marsh bird species. Using generalized linear mixed models, 14 years of marsh bird data were analyzed using Poisson and logistic regression with 6 wetland sites and 5 vegetation cover types to the 11 focal marsh bird species: Pied-billed Grebe (Podilymbus podiceps), American Coot (Fulica americana), Common Moorhen (Gallinula chloropus), Sora (Porzana carolina), Least Bittern (Ixobrychus exilis), Virginia Rail (Rallus limicola), Black Rail (Laterallus jamaicensis), Yellow Rail (Coturnicops noveboracensis), King Rail (Rallus elegans), and American Bittern (Botaurus lentiginosus) noted by the Marsh Monitoring Program. Pied-billed Grebe abundance was found to be significantly different among years depending on six wetland sites (P<-0.001). Least Bittern occupancy was positively associated with emergent vegetation (P = 0.013). Least Bittern and Sora occupancy was negatively associated with open water (P =0.009, P = 0.013). American Coot occupancy was positively associated with exposed mud/sand/rock cover and tree cover (P = 0.005, P = 0.007). Understanding habitat associations of focal marsh bird species can improve future management plans for the wetland units at Ottawa National Wildlife Refuge.

Committee: Thomas Crist PhD (Advisor); Jing Zhang PhD (Committee Member); Amelie Davis PhD (Committee Member) Subjects: Environmental Science

Doctor of Philosophy, The Ohio State University, 2003, Evolution, Ecology, and Organismal Biology

I examined three aspects of forest fragmentation to determine how they impact resident and migrant bird species. The first aspect was the relationship between habitat patch area and species presence and richness. I performed an observational study along riparian woodlands to determine the abundance and distribution of bird species and avian guilds. Woodland area better predicted bird species presence than woodland width. In addition, the probability of detection was positively correlated with woodland area for 11 bird species and negatively correlated with woodland area for eight species. A management simulation of woodland riparian corridor width indicated that current management suggestions were inadequate to provide habitat for a variety of Neotropical woodland migrant bird species. In the second aspect of my research, I examined the ability of two species of birds to supplement their habitat requirements by incorporating disjunct habitat patches on either side of a watercourse into a single territory. I found the probability of eastern wood-pewees (Contopus virens) crossing water gaps to reach simulated singing conspecific to be negatively associated with vegetation gap width. Red-eyed vireos (Vireo olivaceus) demonstrated no significant trend. However, the strength of red-eyed vireo vocal responses after crossing was inversely proportional to the width of waterway. These results suggest that species may differ in their response to simulated conspecific vocalization, and that water gaps less than 30 m wide may not hinder all avian species from crossing to reach playbacks, but may still curtail territorial responses. The third aspect of my work was to determine the ability of a species to colonize empty habitat patches. I simulated patch extinction events by removing Carolina chickadees (Poecile carolinensis) from woodland fragments. I found that chickadees arrived sooner in woodlots connected to other woodland by habitat corridors. I also found that individual c (open full item for complete abstract)

Committee: Thomas Grubb (Advisor) Subjects: Biology, Ecology