Things will get a little batty in Old Sacramento Saturday when Trail Mix and a wildlife rescue group team up to educate people about bats.

Corky Quirk, founder of Northern California Bats, will bring live, wild bats to help dispel some of the myths about these nocturnal creatures. She will also teach people about the benefits and habits of the mysterious winged mammals in a presentation from 1-3 p.m. at Trail Mix, a store selling outdoor merchandise for kids and parents at 116B I St., across from the California State Railroad Museum.

Thousands of bats roost in the nooks and crannies of the city. In summer, a colony of 150,000 to 200,000 bats live under the Yolo Causeway and may be seen flying into the night sky.

California is home to 24 species of bats. Many winter in other countries. Quirk rehabilitates injured and orphaned bats. She will bring two of those most commonly found in the Sacramento Valley: the Brazilian or "Mexican" Free-Tailed bat, which has a 12-inch to 14-inch wingspan, and a Big Brown bat, which has a 13- to 16-inch wingspan and is often seen flying around city lights.

"The one people in Sacramento are most likely to come in contact with are Mexican Free-Tailed bats," Quirk said. "They live all over Old Sacramento in all those old buildings."

The Free-Tailed bat has an obvious tail, an erratic flight and appears precisely at sunset. Their colonies easily number in the thousands. Big Brown bats are harder to spot because their maternal colonies are so much smaller — usually numbering about 20, she added.

Others just as common to the valley include Pallid bats, Western Red bats, Hoary bats, and California and Yuma Myotis bats, which often roost behind signs or under bridges.

The largest bat in California is the Mastiff, which has an 18-inch wingspan. Bats living in the Sacramento Valley have wingspans ranging from 9 to 16 inches. But the bodies are only about 3 to 5 inches long.

"Usually, the thing that people comment the most about is they have no idea how small they are," Quirk said. "They're tiny little animals, and in the United States, all they eat are bugs."

For more information, contact Sara and Mike Barlow at Trail Mix at 498-9090 or Northern California Bats at 530-902-1918. Photos provided by Northern California Bats.