A trail of some of the 40,000 Mexican free-tail bats colonizing the Campbell Bridge over the Rillito River make their home swarm into the stormy skies over Tucson, AZ., Sat., Sept. 12, 2009 at Bat Night.

Kelly Presnell/Arizona Daily Star

The community is invited to welcome the bats home after their winter vacation.

Bat Night is at 6 p.m. Saturday in the Rillito riverbed, east of the Campbell Avenue bridge.

The event features Barbea Williams Performing Company, who will be doing a special "Bat Dance" with the 4th and 5th grade students from Rio Vista Elementary School, accompanied by special musical guests.

Bat expert, Yar Petryszyn, Ph.D. will share his expertise on bats and Entomologist Carl Olson will speak about the insects that bats eat.

For the grand finale, attendees will have the opportunity to watch thousands of bats fly out of their summer home underneath the bridge to find food.

All are encouraged to bring a flashlight, drinking water and a blanket to sit on.  Access the riverbed using the ramp located on the southeast side of the bridge.

There is no cost to attend Bat Night.

For more information, call 304-9532.