Spanning The Gap Between Urban and Ecological Design
What if a bridge could do more than move people from one side to another? What if bridges offered habitats, pest control, tourist attractions, and a boost to the local economy? Then, let me introduce you to bat bridges – a seemingly normal bridge that, intentionally or unintentionally, provides nesting cavities for bats – it’s a supercharged bat house!
The Congress Avenue Bat Bridge
Austin, Texas’ Congress Avenue Bridge is undoubtedly the world’s largest and most famous bat bridge:
When engineers reconstructed the Congress Avenue Bridge [Austin, Texas] 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…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…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. – Bat Conservation International
With construction underway, it’s unlikely that Edmonton’s Walterdale Bridge will include bat habitat. Heck, the concept may not be suitable for Northern bat species. Austin is home to Mexican Free-Tailed bats, whereas Alberta hosts nine smaller varieties of bats. That being said, these examples help reimagine our built environments as safe havens for the natural world.
Contrary to common perceptions, cities can be islands of biodiversity. We have the power to create and partner with ecological systems in mutually beneficial ways.
If you’d like to attract bats to your city, town, or yard, you can find some bat house plans on the Alberta Bats website.