This time of year, female bats are getting ready to have their pups. They’re seeking out darker, hot places like woodlands, and even peoples’ barns, attics or sheds, to give birth.
Holly Niederriter, a wildlife biologist with Delaware's Department of Natural Resources and Environmental Control’s Division of Fish & Wildlife, says it’s pretty common for cave bats like little browns and big brown bats to set up shop in an attic or barn.
“I think the main reason is it just provides sort of a perfect opportunity for them,” Niederriter said. “It’s nice and hot, it’s pretty stable, stable conditions, they’re generally not disturbed there until of course they are.”
Indoor spaces often provide more room for bats to have larger colonies than a typical tree does. Niederriter said pups are born without fur and they’re vulnerable, so the females must find a warm place to raise their young
“And some of our human buildings really do a great job of that for them,” she said.
DNREC says residents who might have bats roosting in their home should complete a bat exclusion before May 15, before bats have their pups. It’s a non-invasive way to get the bats to fly out, without using chemicals.
But Niederriter says if an exclusion is performed after the pups are born, the female bats can fly out, but as the pups are helpless, they won’t be able to follow their mothers, nor can the mothers get back in to tend to their young.
“They need their mother’s milk to survive,” Niederriter said. “Without that they will die.”
Nine species of cave bats and tree bats call Delaware home.
Best management practices for bats can be found on DNREC’s website.