100,000 Bats Will be Evicted by Austin’s I-35 Expansion Project

Austin's I-35 expansion project is set to impact roughly 100,000 bats currently residing in overpasses along the stretch of highway.

Feeling Batty in Austin

According to reports from KUT News, the I-35 expansion is a part of TxDOT's multibillion I-35 Capital Express project. This massive undertaking is making progress, but they have hit a roadblock. At least four bat colonies are located under I-35 in city locations like Howard Lane, Wells Branch Parkway, and Onion Creek.

Luckily for the bats, TxDOT is keeping their presence in mind as they continue operations. New bridges will be built but not before proper precautions are set to ensure the safety of each colony, totaling an estimated 100,000 winged rats in total.

Austin Bat Eviction and Replacement

Through a process called "exclusion", workers will administer an expanding foam into crevices and entrances that bats frequently use. The foam that will be used once the bats leave their roosts for the night will seal any openings so construction can resume.

As effective as this may be, conservationists are not on board due to the risk of sealing bats inside alive. Another risk is that the foam may break off in pieces and fall on unsuspecting drivers.

A second option that is slightly more preferred is installing one-way tubes inside colony entrances that allow bats to leave but not return.

In addition to displacing bat colonies, TxDOT is working towards alternate housing for all of the bats that will not longer have a home. Artificial roosts, 36 of them, were installed over Walnut Creek in Austin.

These 4x4x2 boxes cost roughly $4,000 each, and they take about a year to be utilized by the homeless bats. Other issues include the fact that the roosts are lower to the ground than bats typically prefer, and there are not enough artificial roosts for the sheer volume of displaced bats.

Austin will have to get used to seeing bats more than usual at night until the colonies can find a permanent home as the project continues, but it sounds like they have a few options for substitute roosts in the meantime.