Harvestman. Photo by: J. Krejca
Sixteen species of karst invertebrates are listed as endangered in Travis, Williamson, and Bexar Counties, Texas. All of these invertebrates are troglobites, spending their entire lives underground. They are characterized by small or absent eyes, pale coloration, and attenuated appendages (legs). Their habitat includes caves and mesocavernous voids in karst (landforms and subsurface features, for example, sinkholes and caves, produced by dissolution of limestone bedrock). Within this habitat these animals depend on high humidity, stable temperatures, suitable substrates (for example, spaces between and underneath rocks), and surface-derived nutrients. Examples of nutrient sources include leaf litter fallen or washed in to the subsurface, animal droppings (for example, cave crickets), and animal carcasses. It is imperative for the conservation of the species to understand that while these species spend their entire lives underground, their ecosystem is dependent on the overlying surface habitat.
The primary threat to these species is habitat destruction. Caves and karst habitat are destroyed or impacted in several ways, including but not limited to:
- completely filling the cave with cement or other materials during development
capping or sealing cave entrances
altering drainage patterns (for example, paving over soil and cave entrances, reducing water input)
- altering native surface plant and animal communities, reducing or increasing nutrient flow
comptetition from non-native, invasive vegetation species with native surface vegetation
- excessive human visitation; and
- red-imported fire ants (Solenopsis invicta) competition with cave crickets and predation on karst invertebrates.
The following links are provided to help you understand the life history and Federal listing status of karst invertebrates in Travis, Williamson, and Bexar counties.
Recovery Plan for Endangered Karst Invertebrates in Travis and Williamson Counties, Texas
Bexar County Karst Invertebrates Recovery Plan
Bexar County Karst Invertebrates Distribution (203 KB, PDF)
Karst Preserve Design Recommendations (285 KB PDF, revised 2/28/2012)
Karst Preserve Management and Monitoring Recommendations (160 KB, PDF)
Karst Invertebrate Habitat Requirements (109 KB, PDF)
Karst Invertebrates Taxonomy (1 MB PDF, revised 10/17/2016)
Karst Zone Maps and Reports
Travis/Williamson County Karst Zones (zipped shapefiles, see "Revision of Karst Species Zones for the Austin, Texas Area" document below for more information about the zones)
Revision of Karst Species Zones for the Austin, Texas Area (1.2 MB, PDF)
Travis and Williamson County Karst Zone and Salamander Critical Habitat Mapper (Web Link - This mapper includes Karst Fauna Regions and Critical Habitat for the Jollyville Plateau and Austin Blind Salamanders as well. Note that this application works best in Internet Explorer 9 or above, or the latest versions of Chrome, Firefox or Safari browsers.) Please read disclaimer before using this application.
Bexar County Karst Zones (zipped shapefiles, see "Delineation..." document below for more information about the zones)
Delineation of Hydrogeologic Areas and Zones for the Management and Recovery of Endangered Karst Invertebrate Species in Bexar County, Texas (316 KB, PDF)
Bexar County Karst Zone Mapper (Web Link - This mapper includes Karst Fauna Regions and Critical Habitat as well. Note that this application works best in Internet Explorer 9 or above, or the latest versions of Chrome, Firefox or Safari browsers.) Please read disclaimer before using this application.
Karst Invertebrate Surveys
United States Fish and Wildlife Service, Section 10(a)(1)(A) Scientific Permit Requirements for Conducting Presence/Absence Surveys for Endangered Karst Invertebrates in Central Texas - revised 05/21/2015 (308 KB, PDF)
List of individuals that have a valid permit to survey for endangered karst invertebrates (40 KB, PDF)
Travis/Williamson County Karst Invertebrates
Bexar County Karst Invertebrates
Coffin Cave mold beetle (Batrisodes texanus) and the Bone cave harvestman (Texella reyesi) 58 FR 43818 43820
5-year Status Reviews:
Bone Cave harvestman (Texella reyesi)
Tooth Cave ground beetle (Rhadine persephone)
Tooth Cave Spider (Neoleptoneta myopica), Kretschmarr Cave mold beetle (Texamaurops reddelli), and Tooth Cave pseudoscorpion (Tartarocreagris texana)
Bee Creek cave harvestman (Texella reddelli)
Coffin Cave mold beetle (Batrisodes texanus)
Nine Bexar County Karst Invertebrates
2012 Final Rule designating Critical Habitat for the Nine Bexar County Karst Invertebrates (77 FR 8450 8523) (16.7 MB, PDF)
Critical Habitat Maps and Data:
Link to Critical Habitat Report website - This website has both an online mapper and links to download critical habitat for individual species across the United States.
Our Maps and Data page also has links to online mappers showing Bexar County critical habitat along with karst zones and karst fauna regions as well as karst zones and karst fauna regions for Travis and Williamson Counties.
United States Fish and Wildlife Service white-nosed bat syndrome website