Batty Image: Alabama's Bat Hibernation Cave

bats, flying, fern cave national wildlife refuge, alabama — (Image credit: USFWS.)

Halloween has come and gone, but for Alabama's Fern Cave National Wildlife Refuge, some night stalkers will be hanging around through the winter.

Between 800,000 to 1 million gray bats winter at Fern Cave, located in the northeastern part of the state near Huntsville. Fern Cave is the largest known hibernation cave for this species, which thrives in the southeastern United States. Scientists also suspect some 1 million Indiana bats — a medium-sized mouse-eared bat native to North America — also winter here.

Bats get a bad wrap as the shape-shifting creatures of vampire lore, but only three species of bats suck blood. Most eat insects — small bats can eat up to 2,000 insects every night, keeping crops healthy.

About 30 percent of bat species eat fruit, pollen or nectar. A number of popular foods need bats for pollination, including bananas, dates, coconuts, cloves, vanilla, Brazil nuts and avocados. A Halloween staple — chocolate — also depends on bats, which spread seeds for the nuts, figs, allspice and cacao from which chocolate is made. Fruit bats eat the cacao fruit and discard the bean, which grows into a new tree.

There are more than 1,100 species of bats and they can be found on every continent except Antarctica.

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Brett Israel was a staff writer for Live Science with a focus on environmental issues. He holds a bachelor’s degree in biochemistry and molecular biology from The University of Georgia, a master’s degree in journalism from New York University, and has studied doctorate-level biochemistry at Emory University.