Research Project Details
|Project Title:||Evaluating amphibian distribution models and the importance of small, temporary wetlands on maintaining amphibian diversity in the Delaware Water Gap National Recreational Area|
|Investigator(s):||J.T. Julian and R. P. Brooks, Pennsylvania State University, C.D. Snyder and J.A. Young, U.S. Geological Survey Leetown Science Center|
|Sponsor:||U.S. Geological Survey: Park Oriented Biological Support Program 2005, and National Resources Preservation Program 2006-2007|
Research Project Objectives:
The primary objective of this study is to determine the importance of small wetlands (< 1ha) on the diversity patterns of pond-breeding amphibian assemblages in the Delaware Water Gap National Recreation Area (DEWA). To accomplish this, we are creating a comprehensive map of potential breeding habitats throughout the Park, and sampling selected wetlands to generate models that predict the use of these habitats by amphibian species.
Smaller wetlands are disproportionately important in terms of their abundance in the Park, yet they are difficult to identify using aerial photography (see map). Furthermore, while there is generally a positive relationship between wetland size and the probability a species will breed in a wetland, size needs to be considered in the context of hydrologic (stream) connectivity to predict the presence of some species (see graph). These empirically derived relationships will be used to develop spatially-explicit models to predict the responses of amphibian assemblages to the losses of various sized wetlands across the landscape.
These data can be used by DEWA natural resource managers to predict the location of critical amphibian breeding habitats and evaluate the use of small, seasonal wetlands as candidate habitats for long-term monitoring initiatives.
- Snyder, C.D. and J.T. Julian. 2006. Importance of small wetlands to the diversity of amphibian assemblages in the Delaware Water Gap National Recreation Area. National Park Service Investigators Annual Report #35189. Submitted March 2006. Available at this link.
- Snyder, C.D., J.A. Young, and J.T. Julian. 2007. Ecological impacts of development in areas surrounding Delaware Water Gap National Recreation Area. National Park Service Investigators Annual Report. Submitted March 2007.
- Snyder, C.D. and J.T. Julian. 2007. Importance of small wetlands to the diversity of amphibian assemblages in the Delaware Water Gap National Recreation Area. National Park Service Final Report. Summer 2007.
- Snyder, C.D., J.A. Young, and J.T. Julian. 2008. Ecological impacts of development in areas surrounding Delaware Water Gap National Recreation Area. National Park Service Final Report. Summer 2008.
- Geographic Information System (GIS) datalayer of potential amphibian breeding habitats in DEWA attributed by wetland size and hydrologic connectivity, and a detailed account of amphibian assemblages at > 20% of these wetlands.