After their winter trip south, Mexican free-tailed bats are returning to the Bracken Bat Cave in Central Texas in larger numbers, which is good news for South Texas agriculture.
Millions of Mexican free-tailed bats make their summer home at the Bracken Cave just north of San Antonio, and farmers in South Texas rely on them to swarm across their farmland and eat the insects that can destroy crops.
Andy Walker, executive director of Bat Conservation International, which is headquartered in Austin, said the bats started arriving in mid March and will continue to arrive through the end of April.
“So by the end of April we’ll have well over 10 million pregnant Mexican free-tailed bats in Bracken Cave alone,” Walker said.
Walker said Bracken will grow by another five million to six million baby bats by the end of July. He said Bracken bats have been banded and tracked only as far as southern Mexico, but Mexican free-tailed bats have been found throughout Central America and parts of South America.
Walker said when those pregnant bats return to Bracken, they’ll be hungry.
"Predominantly what they’re going after are moths, and it’s moths that are the biggest risk to American agriculture," Walker said. "They’re eating cotton boll weevil moths and corn borer moths."
Walker said only about 3 percent of a bat's diet consists of mosquitos.
Walker said later this summer, BCI will begin offering nightly viewings of the bats’ exodus from the Bracken Cave, by reservation only. Information on those visits can be found at:
But you can also watch 10 million bats fly out of the cave from the comfort of your own home.