The insect-eating bats over American farmland are worth up to $53 billion a year, and despite that, bats are still among the most misunderstood and feared wildlife in America.
Bats are free pest control working the night shift over cropland, eating the moths and beetles whose larvae chew through corn, cotton, and orchards. A single colony of 150 big brown bats eats about 1.3 million insects a year. Scaled across US agriculture, one study's most likely figure landed near $22.9 billion in free pest control.
Then came white-nose syndrome. The fungal disease, first found in New York in 2006, has spread to 40 states and killed millions of bats, wiping out more than 70% of bats in the colonies it reaches.
What happened next is the part that will really blow you away. A 2024 study in Science by University of Chicago economist Eyal Frank compared counties where bats collapsed to counties where they didn't.
In the collapse counties, farmers made up the lost pest control with chemicals: insecticide use rose 31%. And in those same counties, infant mortality rose nearly 8%, which Frank estimates at 1,334 additional infant deaths between 2006 and 2017, after controlling for other factors that could affect infant mortality.
If you've got bats in a barn or under a bridge nearby, leave them. Don't seal them out in summer, when flightless pups are still inside. Skip the bug zapper and the broadcast yard spraying that hollows out their food.