LARGEST -- World's Largest Urban Bat Colony - Austin, TX
Posted by: 
QuesterMark
N 30° 15.614 W 097° 44.715
14R E 620705 N 3348287
The Congress Avenue Bridge in Austin is home to the World's Largest Urban Bat Colony.
Waymark Code: WM5DAQ
Location: Texas, United States
Date Posted: 12/21/2008
Views: 59
The world's largest urban bat colony is beneath the Ann W. Richards Congress Avenue bridge. The bats reside beneath the road deck in gaps between the concrete component structures.
The bats are migratory, spending their summers in Austin and the winters in Mexico. According to Bat Conservation International, between 750,000 and 1.5 million bats reside underneath the bridge each summer, whereas Austin's population is about 700,000, so, there are more bats than inhabitants in Austin during the summer.
The nightly emergence of the bats from underneath the bridge at dusk, and their flight across Lady Bird Lake primarily to the east, to feed themselves, attracts as many as 100,000 tourists annually. Tourists can see the bats from the bridge, from the sides of the river and even from special boats.
(information from
Wikipedia)
The bridge had a major deck reconstruction in 1980. This new construction created crevices 16" deep running the length of the bridge. Bats live primarily in those that are three quarters to one-and-a-half inches wide. Temperature and humidity conditions within these spaces are idea for raising young.
(information from a sign on site provided by the Austin-American Statesman)