Earth Notes: Spotted Bats

Feb 22, 2017

In the animal world, spotted bats are standouts as endurance athletes. Weighing about as much as four chocolate kisses, these little flying mammals cover a lot of ground. 

Spotted bat
Credit Bruce Taubert

Scientists tracked a nursing mother bat from inside Grand Canyon to the meadows of the North Rim – thousands of feet above and about 25 miles away from her daytime roost. She flew several hours during the night, chasing and eating moths on the wing. Around midnight she snoozed in a tree before zipping home at more than thirty miles an hour. Northern Arizona University bat biologist Carol Chambers likens this to a human nursing mother running back-to-back marathons.      

Unlike many others, spotted bats roost alone in cracks high on sheer cliff faces. Chambers thinks these cliffs, sun-warmed during the day, keep infant bats warm at night while their mothers hunt in the higher, cooler environments and reduce water loss.  

DNA analysis by Chambers and fellow researchers suggests that about 120,000 years ago spotted bat populations were centered around Mexico. Within the last 22,000 years, they made it to the Southwest. When climate warmed, the bats kept moving north. Within the last 6,000 years some were stranded in the Northwest, but the majority now lives in the Southwest.

On the rim of the Grand Canyon soon after sunset, you may hear the soft chirps of spotted bats – echolocating as they conduct amazing athletic feats.