“Bat Colonies Sink Teeth Into City.” That was the Austin American-Statesman’s headline on September 23, 1984, when the town discovered more than a million Mexican free-tailed bats nesting under the Congress Avenue Bridge. Accompanying the story was an image (above) of the winged mammals flying above Lady Bird Lake (then Town Lake) with a caption detailing how they “flit eerily under a cloak of darkness.”

The bats hadn’t always been there. Rather, they began accumulating after the bridge’s renovation in 1980, which inadvertently created the perfect roost when a series of inch-wide joints were added along the structure’s undercarriage. Distressed by urban myths and horror stories involving rabies-riddled blood-suckers, Texas’s capital came unhinged. “They come zooming down on people in the pool area in the evenings,” said Mickey Oyston, a hotel concierge. “No one seems to have the answer.”

Austin was torn. The city considered building nets around the bridge to prevent them from settling down, but that idea was nixed when citizens began to worry that the move would push the bats into nearby neighborhoods. Petitions demanding the animals’ extermination began circulating.

Luckily, Merlin Tuttle had the answer. Founder of the Bat Conservation International in Milwaukee, Tuttle swooped into town to assure Austinites that the animals were harmless. Many, including Texas Monthly—which gave him a Bum Steer Award in 1986—were skeptical. Nonetheless, the conservationist persisted, gradually shifting the city’s perspective from panicked to prideful over the years. “It is simply amazing how quickly attitudes improve when people finally understand bats as they really are,” Tuttle later said. To his point: Austin is now the self-proclaimed bat capital of the world