Jewel Cave Conducts Winter Bat Survey

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Date: January 29, 2015
Contact: Bradley Block, 605-673-8330

Custer, SD – Jewel Cave National Monument conducted its annual bat count on Wednesday, January 28. National Park Service staff partnered with the Black Hills National Forest and experienced volunteers to count 1437 bats hibernating just beyond the cave’s historic entrance.

The count included three genera of bats and was one of the highest recorded counts since 2005, which numbered 1555. The most numerous species recorded was the Townsend’s big-eared bat (C. townsendii) numbering 904, followed by various Myotis species totaling 531, and 2 big brown bats (E. Fuscus).

Jewel Cave supports one of the largest known hibernating colonies of Townsend's big-eared bats in the world. The cave provides a safe haven during the winter months, allowing uninterrupted hibernation from predators and human disturbance. Numerous disturbances can exhaust bats’ energy reserves and may have damaging effects on hibernating populations; bats that use up energy during the winter season could die before the spring months. For this reason, Jewel Cave National Monument does not offer the ever-popular lantern tours at the historic entrance during the off-season.

It is important to note that the benefits of bats outweigh the negatives. Vacationers and locals benefit from insect control provided by bats. As an example, many Black Hills bat species feed on beetles, moths, flies, and mosquitoes. A single little brown bat (M. lucifugus) is capable of eating hundreds of mosquitoes in an hour. Cucumber and June beetles, stink bugs, and leafhoppers, all well-known garden pests, are just a few of the many insects known to be consumed by bats during the summer season.

Mike Wiles, Chief of Resource Management, states, “Many visitors are well aware of the underground resources associated with Jewel Cave; however, the monument also provides vital surface habitat for numerous plants and animals. Serving as a hibernation site for a variety of bat species, Jewel Cave is protecting and preserving a part of the region’s unique natural history.”

Jewel Cave National Monument is currently open Mondays through Fridays from 8:30 a.m. – 4:30 p.m., during the winter season. For more information concerning guided cave tours or to learn more about the bats at Jewel Cave, visit the Monument online at or call the visitor center at 605-673-8300.

Last updated: June 29, 2017

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11149 U.S. Hwy. 16
Building B12

Custer, SD 57730


(605) 673-8300

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