Some of us put up "bat houses" to give them shelter.
We can get them in Lowes.
The Bats under the Congress Avenue bridge in Austin Texas are a huge tourist attraction.Every summer night, hundreds of people gather to see the world's largest urban bat colony emerge from under the Congress Avenue Bridge. These 1.5 million bats are fun to watch, but they're also making our world a better place to live.
When engineers reconstructed downtown Austin's Congress Avenue Bridge in 1980 they had no idea that new crevices beneath the bridge would make an ideal bat roost. Although bats had lived there for years, it was headline news when they suddenly began moving in by the thousands. Reacting in fear and ignorance, many people petitioned to have the bat colony eradicated.
As the city came to appreciate its bats, the population under the Congress Avenue Bridge grew to be the largest urban bat colony in North America. With up to 1.5 million bats spiraling into the summer skies, Austin now has one of the most unusual and fascinating tourist attractions anywhere.
The Austin American-Statesman created the Statesman Bat Observation Center adjacent to the Congress Bridge, giving visitors a dedicated area to view the nightly emergence. It is estimated that more than 100,000 people visit the bridge to witness the bat flight, generating ten million dollars in tourism revenue annually.
more info and pictures....
http://www.batcon.org/home/index.asp?idPage=122More info about Bat Watching in Austin.
http://www.austincityguide.com/content/congress-bridge-bats-austin.asp