The U.S. Fish and Wildlife Service maintains the Critical Habitat Mapper, an online service for information regarding Threatened and Endangered Species final Critical Habitat designation across the United States. You can use this service to download information for use in a GIS, or use the mapping functionality to view an area of interest.
Geographic Information System (GIS) Shapefiles for Karst Zones are available for download. Click below and 'Save Target As' to download the desired zip-compressed shapefiles.