Photo by MDC Staff, courtesy Missouri Department of Conservation.
By Allison Hagene
The Missouri Gray Bat once flourished in caves across the southeastern U.S., but since 1976 they have been consistently documented as an endangered species. Living only in an estimated 11 caves across the country, the Gray Bat has been struggling to cope with human encroachment, cave disturbances and diseases in their underground living spaces.
Human disturbance is posing a very real and growing threat to the Gray Bat’s population growth. When humans enter a nursery cave, they can scare mothers who abandon their young which then either die from starvation or fall out of the nest and die on impact. When humans also enter wintering caves, they disturb hibernating bats that, when woken early, use up fat reserves and die from starvation as well. Both issues can collapse a colony’s population and reproduction for the whole year.
Conservation efforts are underway to try to preserve Gray Bat populations, including maintaining and protecting wintering and nursery caves from disturbances, as well as reducing pesticide use in surrounding areas.
Pesticides have damaged on not only bat populations, but whole species of plants and animals across the globe. From birth deformities, to sterilization, to seizure episodes and sudden death, pesticides have caused ill effects across the earth. Aside from pesticides and human carelessness, Gray Bats and other bat populations have been suffering from a new deadly fungal disease called White-Nose syndrome. This disease invades the skin of hibernating bats, and the irritation causes them to wake up during winter hibernating months. This causes them to use their fat reserves rapidly and die of starvation or body temperature drops.
Bats have such a special niche in their ecosystem. They help contain flying bug populations because insects are their main source of food. Bats also provide benefit both in and out of caves. They devour organic material outside (in the form of bugs), and release that matter inside the cave as excrement, which helps provide life for a variety of organisms inside the cave. Without bats our insect populations would not be kept in check and the health of our caves would plummet.
Conservation efforts to keep caves wild does help bat populations to stabilize, but the commercialization of caves has continued to cause problems. Using caves for recreational activities and tours changes the air flow, temperature, humidity, light exposure, and brings in new, foreign contaminants harmful to bats.
Organizations like the U.S Fish and Wildlife Service and the Missouri Department of Conservation have led efforts to get proper gating of cave entrances to deter humans from entering. A variety of other government funded, and private conservation agencies have also stepped in to help preserve population health and growth.
Things the everyday citizen can do to make a difference include – leaving bats and caves alone, reducing pesticides and pollution, encourage others to follow suit, leave nature wild (maintain natural environments), protect water quality in your area, and even put up a bat house to provide shelter for bats near your home.
Gray Bats can be found at cave sites such as:
- Smallin Civil War Cave (Ozarks)
- Mary Lawson Cave (Columbia, now gated)
- Tumbling Creek Cave (Protem)
Other endangered bats in Missouri and their locations:
- Indiana Bat, found in the Ozarks and along rivers and streams in northern Missouri
- Ozark Big-Eared Bat, found in limestone and sandstone talus caves in oak-hickory forests in the Ozark Highlands and also in Arkansas
- Keen’s Myotis, found mostly in the Ozarks, but are now no longer common enough in any one area. They are also known to nest in hollow trees, attics, under siding and shingles, and on cliff crevices. (Found in Mary Lawson Cave, which is now gated for the bats protection)
For more information check out these resources:
https://mdc.mo.gov/discover-nature/field-guide/gray-myotis-gray-bat
https://www.fws.gov/midwest/endangered/mammals/pdf/gray-bat.pdf
https://www.fws.gov/midwest/endangered/mammals/grbat_fc.html
Environmental Echo 