Landscape level predictors of a suite of imperiled wetland associated herpetofauna
Abstract
Wetland and upland habitat loss, habitat fragmentation, and degradation collection pressure, have resulted in legal protection for the Eastern Massasauga (Sistrurus catenatus catenatus), Copper-bellied Watersnake (Nerodia erythrogaster neglecta), Spotted Turtle ( Clemmys gutatta), and Blanding's Turtle (Emydoidea blandingii ) across the entirety of their geographic ranges. To investigate the landscape level predictors for the suite, a large-scale habitat modeling project was initiated. Historical occurrence data was integrated with recent survey data for a total of 147 location points. These points were used in ArcMap 10.0 GIS in conjunction with multiple habitat layers to develop ideal habitat models for use in determining which landscape level variables are of the greatest importance to the suite both collectively and individually. Two models were created, 90 and 50% observation inclusion determining a minimum threshold (t) for being considered valuable. These models encompassed varying portion of the occurrence records so as to determine the strength of correlation of a variable and the suite. Results indicated only a few of the layers explored were shown to be correlated to the presence of the suite. The few layers that showed predictive strength were similar among all species indicating potential overlapping predictors. However, each layer had a different minimum threshold indicating that each species may need a different minimum amount of a variable to present within a habitat to promote the presence of the species.
Degree
M.S.
Advisors
Kingsbury, Purdue University.
Subject Area
Ecology|Environmental management
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