Resource Ramblings 2004-09
Wildlife of the night abound at Wind Cave National Park
As the summer season winds down, we thought you might be interested in some Park research begun in August. Mist nets were set up at five locations in the
The availability of areas for bats to hibernate, proximity to foraging areas, abundance of water sources, and an abundance of summer and maternity roost sites makes the Black Hills excellent habitat. A number of migratory species, such as silver-haired bats, are documented to use the Black Hills for summer activities, including maternity roosting. With this, the Black Hills represents an island ecosystem within the mixed- and short-grass prairie/pastureland matrix of western South Dakota and eastern Wyoming.
During the first round of surveys, we were able to document 10 of 11 species of bats suspected as users of the park’s habitats. All of these species are listed as being residents in the Black Hills, but not all had been documented in the park before. In addition, we were able to add a new species to the park’s species list, red bat. The following is a list of the species found:
In addition, acoustic surveys were conducted at sites to collect travel and search calls, as well as feeding buzzes. Without using their vision (which they have), many bats can find food and avoid obstacles with great ease, by use of echolocation or sound waves. An Italian scientist, Lazarro Spallanzani, living in the late 1700s, helped us begin to understand how bats operated in the dark. He placed a bat and an owl in a semi-dark room and found that both could orient well in low light. In complete darkness, the bat flew effortlessly while the owl bumped into objects in its flight path. When he placed a sack over the bat's head, it too, became disoriented. Spallanzani concluded that bats used a "sixth sense" to orient and after revising his experiments, concluded that bats could “see” using their ears and sound. The sounds we recorded will be analyzed this fall and help in developing an electronic library of language for each species of bat within the park and Black Hills.
Four species documented (Northern long-eared myotis, Fringe-tailed bat, Silver-haired bat, and Townsend’s big-eared bat) are listed as South Dakota species of concern and four (Townsend's Big eared bat, Fringe-tailed myotis, Long-legged myotis, and Western Small-footed myotis) are listed as species of concern by the U.S. Fish and Wildlife Service.
So what is so important about bats and why should we care? Well, consider these facts:
Bats are an integral part of the ecosystem, filling a niche not utilized by other species. However, the most significant threat to bat survival and their vital ecosystem role are human persecution and loss of habitat. Vandalism and disturbance of roosting caves, loss of tree snags, and careless use of pesticides all seriously threaten bat populations.
Comments and feedback about Resource Ramblings are encouraged and can be made via email.
Did You Know?
Winds caused by changes in barometric pressure are what give Wind Cave its name. These winds have been measured at the cave's walk-in entrance at over 70 mph. The winds at the natural entrance of the cave attracted the attention of Native Americans and early settlers.