Celebrating groundwater and cave critters

Endangered Species Bulletin, Dec, 2004 by Theresa Jacobson

What do endangered cave critters, drinking water, and fourth graders have in common? They are all linked by a two-day festival held each spring in Madison County, Alabama.

For the past six years, the U.S. Fish and Wildlife Service has teamed up with the Huntsville Grotto and U.S. Army's Redstone Arsenal to present "Hungry Cave Critters," an activity involving endangered cave species, to excited fourth graders attending the festival. Students play the roles of various cave critters, including cave crayfish, cave shrimp, and cave salamander. Crawling on the carpet floor of a darkened room, the students search for food cards. Competition for food is fierce; their critter won't survive if the students can't find enough food.

Bats play a key role in a cave's food chain due to their droppings, called guano. Bat guano is an important food source in caves and is eaten by microscopic invertebrates, cave insects, cave crayfish, and cave fish. During the second round of the Hungry Critters activity, our imaginary cave has been vandalized, causing the endangered bats to abandon the cave and thereby upsetting the amount of available food. Many more cave critters die in the game because of the missing guano in the food chain.

After two quick rounds of food gathering, the students learn about the variety of animal species that live underground and glean insight into their fragile cave habitat. Water festival educators emphasize the four endangered cave animals that live in northern Alabama: the gray bat (Myotis grisecens), Indiana bat (Myotis sodalis), Alabama cave shrimp (Palaemonias alabamae), and Alabama cave fish (Speoplatyrhimus poulsoni).

Students also learn that groundwater is an important source of drinking water for people in Alabama as well as other areas of our country. Clean groundwater supports a diversity of aquatic cave animals. Cave fish and cave shrimp living in groundwater streams and pools are indicators of water quality. If aquatic cave species suddenly disappear from their environment, that's a warning of possible groundwater contamination.

Before the students leave, they watch a video clip taken from inside a cave on the Redstone Arsenal. Tiny, translucent Alabama cave shrimp swim in a pool along with ghostly-white cave crayfish and pink-tinged cave fish in their underground world. In about 25 minutes, the fourth graders have learned about endangered cave critters and how their drinking water and the groundwater below their feet are all interconnected in the fragile karstlands of north Alabama.

Theresa Jacobson, a wildlife biologist and outreach specialist in the Service Jackson, Mississippi, Field Office, can be reached at terri_Jacobson@fws.gov or (601) 321-1129.

For more information about the Madison County Drinking Water Festival, visit the web site at http.// www.hsvutil.org/drinkingwaterfestival/ index.htm.

The activity "Hungry Cave Critters" is published in Project Underground, a natural resource education guide. (http:/ /www.dcr.state.va.us/underground.htm).