Finding ways to reconcile the habitat needs of people with those of wildlife is of great importance for preservation of species diversity. The objective of this study is to examine how land-use in a human dominated landscape affects where wild species occur. These "distributions" of wild species depend on availability of two types of habitat: habitat where populations can grow and persist, and habitat that connects populations to allow for dispersal. Changes in land-use can affect both types of habitat, yet most research has considered just the first type. This study focuses on how habitat connectivity impacts the growth and survival of frog populations. In doing so, it will provide research training for graduate and undergraduate students. Findings from this study will be used to create educational materials for elementary school students, who will learn about how habitat connectivity affects animal dispersal. The investigators will collaborate with the Hefner Museum of Natural History at Miami University to create a display explaining how patterns of human land-use affect wildlife. Finally, the methodology developed for this study may provide the basis for species management plans.
Specifically, the goal of this project is to test the hypothesis that landscape connectivity explains discrepancies in a species? realized versus potential distribution, based on availability of suitable habitat. Using cricket frogs (Acris blanchardi) as a model system, investigators will address the following aims: (1) assess which land-use and environmental factors are most important for habitat suitability and are predictive of species presence, (2) determine the current eastern edge of the range and whether there is a discrepancy between the actual cricket frog distribution and the distribution of suitable habitat (potential distribution), and (3) assess whether a gradient in landscape connectivity from the interior to edge of the range can explain differences in realized and potential distributions. Aims 1 and 2 will be addressed using ecological niche modeling and ground-truthing surveys. The niche model will use presence data from previous surveys and include both climatic and land-use data layers. Aim 3 will be addressed by incorporating niche model results in landscape connectivity analyses based on graph theory. Connectivity will be compared between the interior of the range, the range edge, and outside the range. Due to recent contraction and expansion of the cricket frog range boundary, investigators predict areas of suitable habitat outside the current range. Low levels of landscape connectivity at the range boundary and outside the range are predicted to explain why cricket frogs are unable to occupy their entire potential range.
