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Management Guidelines for Karst Invertebrates Preserve Known Cave Sites The karst features inhabitated by these species and the ecosystems on which they depend have evolved slowly over millions of years. Once destroyed, they cannot be recreated. Protection of these ecosystems will require maintaining moist, humid Cave entrance © USFWS Ruth Stanford Cave entrance 0 George Veni conditions and stable temperatures in the air spaces; maintaining an adequate nutrient supply; prevent- ing contamination of the water entering the system; and preventing or controlling invasion of exotic species, such as fire ants. Preservation of known caves, fissures, and other karst features is important to maintaining this unique ecosystem and the animals that live there. Building and road construction should be avoided in the vicinity of known caves and cave entrances. These entrances should not be filled because input of nutrients and surface water is important in maintaining the sys- tem. Where cave entrances are large enough to pose a hazard to humans or livestock, they can be fenced or gated to restrict access by large animals yet allow movement of raccoons, small mammals, insects, and water into the cave. Avoid Altering Surface Drainage Patterns Landowners should avoid altering surface drainage patterns in the vicinity of known caves. Because karst ecosystems depend on air spaces with some water infiltration, diverting water away from a cave could result in drying and death for the cave and for many cave animals. Also, too much water can lead to flooding and loss of air - breathing species. Altering the quantity of water inflow can also result in changes in the nutrient input. Preserve Native Vegetation Maintaining native vegetation in areas containing karst features is important. When native vegetation is destroyed or replaced by intro- duced plants, the overall species diversity declines. Many of these plants and animals may be critical to the nutrient regime of the karst ecosystem, and their loss could lead to nutrient depletion. By maintain- ing native surface vegetation in the vicinity of karst features, landown- ers can help minimize temperature fluctuations, maintain moisture regimes, reduce potential for conta- mination, and reduce sedimentation from soil erosion. Prevent Groundwater Contamination Because karst is highly susceptible to groundwater contamination, the proper use and disposal of chemi- cals such as pesticides, motor oil, and household chemicals is very important. The use of broadcast pesticides, either liquid or granular, should be avoided in areas near known cave entrances or other karst features. Restrict Human Visitation Landowners can protect cave sys- tems by restricting access and thereby reducing human visitation and impacts. Detrimental human impacts include habitat disturbance or loss due to soil compaction, changes in temperature and humid- ity, vandalism, abandonment of the cave by associated surface animals, and accumulation of toxic trash such as alkaline batteries. Control Fire Ants Although the full impact of fire ants on the karst ecosystems is not known, fire ants are believed to be a serious and increasingly impor- tant threat to the karst fauna. Controlling fire ants in areas sur- rounding cave entrances may help minimize their impact on the cave fauna. Effective treatments include hot water and commercial fire ant baits. At present, there is little infor- mation available on the impacts that chemical methods of fire ant control used on the surface have on species that live exclusively under- ground. Because of this lack of information, the U.S. Fish and Wildlife Service (USFWS) recom- mends that only boiling water treat- Karst Invertebrates Management Guidelines 122