Bats are worth their weight in gold, so to speak.
Overall, bats prevent $3.7 billion a year in crop damage and pesticide use in the U.S., according to Bat Conservation International, a group dedicated to promoting bats.
For example, cucumber beetles eat spinach and corn, and their larvae, corn rootworms, can reduce corn yields by up to 13 percent.
But a single big brown bat (Eptesicus fuscus), a species found in Idaho, can have a heavy impact on the rootworm population. The bat — one of the largest in the U.S. — weighs a mere .5 to 1.2 ounces. But agronomists estimate a colony of 150 big brown bats will eat 38,000 cucumber beetles in a single growing season, preventing the beetles from producing 18 million corn rootworms.
Corn rootworm control costs about $25 per acre to do what big brown bats do for free.
Bats are also important pollinators.