Environmental Karst Site Assessment, Camp Bullis, Texas: Maneuver Areas 8, 9, 10, and 11, and Southern Cantonment 144
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MANAGEMENT PLAN FOR THE CONSERVATION OF RARE AND ENDANGERED KARST SPECIES, CAMP BULLIS, BEXAR AND COMAL COUNTIES, TEXAS by George Veni Ph.D., James R. Reddell, and James C. Cokendolpher Executive Summary Camp Bullis is a 113.3-km2 military training facility under the Fort Sam Houston Command. It is located in north-central Bexar County and southwestern Comal County. Camp Bullis’ mission is to provide field training and support for military activities in south Texas, including weapons training, field training and maneuvers, map and compass courses, parachute operations training, combat assault landing training, and field medical training. Soon after the now-listed species were petitioned for endangered listing, Camp Bullis initiated a series of cave and karst investigations that continue to the present in order to pro-actively evaluate the installation’s potential to contain the species and manage those species according to the best available scientific information (Veni and Elliott, 1994; Veni et al., 1995, 1996, 1998a, 1998b, 1999, 2000, 2002a, 2002b). To date, three of the species have been found on the installation, Cicurina (Cicurella) madla, Rhadine exilis, Rhadine infernalis. Additionally, one species on the State of Texas list of threatened species has been found, Eurycea tridentifera, plus 15 new or possibly new species known only from Camp Bullis. The presence of these listed and rare species of concern suggests that Camp Bullis has effectively managed its impact to the environment and these animals. This includes the potential impacts from the installation’s live fire ranges where one of the listed species is known to occur in five caves despite several decades of firearm use. With the increasing rate of urban development of the area around the installation, Camp Bullis may become an important refuge where these and other listed and rare species will continue to survive. The mission requirements of Camp Bullis demand the presence of large tracts of undeveloped land for training operations that are mostly compatible with successfully preserving in perpetuity the ecosystems of the listed species and species of concern. This management plan is designed to minimize and/or direct potentially detrimental impacts away from those species where feasible, including impacts (like fire ant infestation) not resulting from Camp Bullis actions. Where impacts to the species cannot be avoided, Camp Bullis will enter into consultations with U.S. Fish and Wildlife Service (USFWS). This management plan represents the cumulative efforts of Camp Bullis to eliminate, mitigate, and prevent harm to the four federally or state-listed species and the 15 rare but unlisted species of concern. All of the species are troglobites, known only from caves and related karst voids, and all but the state-listed species are invertebrates. Most of the species are known only from Camp Bullis. 1 This plan is written in the format of a USFWS recovery plan to best address past and current threats and management actions, and to efficiently propose and coordinate future management action for the species, including an Endangered Species Act Section 7 consultation if necessary with USFWS for the listed species. By proposing a plan that includes non-listed species of concern, Camp Bullis can take a broader and more effective ecosystem-based approach to species management, similar to habitat conservation plans. This management plan is designed to provide detailed steps for management of the listed karst species and species of concern at Camp Bullis and to outline a general strategy for situations not covered by specific management actions. The management plan has two goals: 1) preservation and protection of the listed karst species and species of concern and their habitat in perpetuity, within the limits possible through the caves, land, and authority of Camp Bullis and its operational and mission requirements; 2) ensure the species’ survival, genetic diversity, and evolution in a manner consistent with the delisting or downlisting of endangered and threatened karst species as recognized by the USFWS (1994) recovery plan for related listed species in the Austin, Texas, area. Below is an outline of the tasks needed to meet the objectives of this plan. Narrative descriptions of the tasks are discussed in the plan followed by specific management recommendations for the 32 karst management areas. Attainment of this plan will proceed as allowed by funding and Camp Bullis’ mission and operational requirements. 1. Identify karst management areas needed to meet the management plan criteria. 2. Determine the appropriate size and shape of the karst management areas. 3. Provide protection in perpetuity to the karst management areas. 3.1 Coordinate with USFWS, TPWD, and other agencies. 3.2 Review and update Camp Bullis regulations as needed. 4. Implement conservation measures and manage karst management areas. 4.1 Apply USFWS fire ant management techniques. 4.2 Identify and protect important sources of nutrients into karst ecosystems. 4.3 Determine and implement appropriate means to prevent siltation and/or entry of other contaminants to the karst management areas. 4.4 Determine and implement appropriate means to prevent vandalism, dumping of trash, and unauthorized human entry of caves and karst features. 4.5 Other actions as needed. 5. Additional research. 5.1 Conduct additional karst and biospeleological surveys. 5.2 Continue hydrogeologic studies of karst management areas that are currently incomplete. 5.3 Conduct additional studies on the ecology of the listed species and species of concern. 5.4 Revise the karst species management plan as needed. 6. Education 6.1 Develop educational programs to raise awareness and encourage protection of karst ecosystems by Camp Bullis personnel. 6.2 Develop educational programs on karst ecology and hydrogeology to help 2 key Camp Bullis personnel with the management of the karst management areas and the listed species and species of concern. 6.3 Develop educational information for public relations. 7. Monitoring The one notable management issue involves the ability of Camp Bullis to redirect the training at the live fire ranges. Reorienting these firing areas is not feasible within the current Army training doctrine or funding level of the installation. Activities on the ranges that could have a detrimental effect are accidental fires that destroy native vegetation, mowing around the target arrays, bullet strikes around and near cave entrances that damage the vegetation, and the release of potentially harmful levels of heavy metals to the environment. Camp Bullis will mitigate these possible impacts by undertaking the following actions on the live fire ranges: 1) Any accidental range fire will be fought vigorously in the area around any cave on a live fire range to limit the impact to the smallest possible area. 2) A buffer area of 10 meters will not be mowed around cave entrances on the live fire ranges. 3) Camp Bullis will continue to monitor water leaving the live fire ranges for contaminants that may prove detrimental to the cave species. 4) Camp Bullis will enter into consultation with the USFWS if there is a major increase in training activity near any cave with listed species. 3 Introduction The Bexar County, Texas, region is hydrogeologically and biologically complex. Species living in the region’s caves have become physically isolated from each other through time, resulting in genetic isolation that has produced new species known to occur only within small geographic areas. The northward expansion of San Antonio onto the karst areas where these species occur poses a threat to their survival. This is due to the destruction of caves, sealing of caves, changes in nutrient and moisture input into caves, contaminants introduced into caves, and competition with and predation by non-native species introduced by urbanization (Elliott, 1993a, 2000). Due to concern about their survival, nine species of karst invertebrates were federally listed as endangered by the U.S. Fish and Wildlife Service (USFWS) in December 2000 (USFWS, 2000a), with critical habitat proposed in August 2002 (USFWS, 2002): Batrisodes (Excavodes) venyivi Neoleptoneta microps Cicurina (Cicurella) baronia Rhadine exilis Cicurina (Cicurella) madla Rhadine infernalis Cicurina (Cicurella) venii Texella cokendolpheri Cicurina (Cicurella) vespera These species are currently only known from northern and parts of western Bexar County. Camp Bullis is a 113.3-km2 military training facility under the Fort Sam Houston Command. It is located in north-central Bexar County and southwestern Comal County. Camp Bullis’ mission is to provide field training and support for military activities in south Texas, including weapons training, field training and maneuvers, map and compass courses, parachute operations training, combat assault landing training, and field medical training. Soon after the now-listed species were petitioned for endangered listing, Camp Bullis initiated a series of cave and karst investigations that continue to the present in order to pro-actively evaluate the installation’s potential to contain the species and manage those species according to the best available scientific information (Veni and Elliott, 1994; Veni et al., 1995, 1996, 1998a, 1998b, 1999, 2000, 2002a, 2002b). To date, three of the species have been found on the installation, Cicurina (Cicurella) madla, Rhadine exilis, Rhadine infernalis, plus 15 new or possibly new species known only from Camp