Hundreds of bats rescued from the winter storm that struck the US over the past week were finally able to return to their homes in Texas last night. The bats nearly froze to death as the storm brought a blast of cold Arctic air down to the Lone Star State and much of the continental US.

Mexican Free-tailed bats started dropping from their roosts as temperatures dipped below freezing on the evening of December 22nd, according to the Houston Humane Society. At one colony under Waugh Bridge in Houston, the tiny bats plummeted 15 to 30 feet to the pavement. Suffering hypothermic shock, the bats might have perished on the pavement. Weighing in at around half an ounce, the critters don’t have much body fat to keep themselves warm.

But the Houston Human Society quickly jumped into action with a “cold-shock” bat rescue initiative at Waugh Bridge and another colony in Brazoria County. You can check out some neat videos of the effort on the Houston Humane Society’s Facebook Page. “Amazingly, most of bats have survived,” the group said on Facebook on December 24th. By December 26th, they had rescued 1,544 bats.

While more than 50 of the bats were in need of “more intensive care,” most of them “only required heat support & hydration to quick start their systems,” the Houston Humane Society said in a Facebook post. “They will be held, receiving specialized care and nutrition, until the weather warms and release is possible.”

Fortunately, the weather was just right for their release yesterday. The Human Society even set up a Facebook event to invite the public to watch the bats’ homecoming. Some 700 bats were brought back to their colony under Waugh Bridge Wednesday evening. “Hundreds” more were returned to a separate colony at the Pearland Fite Road Bridge in Brazoria County.

But even after this success story, the Houston Humane Society is readying itself for future weather disasters. Its Texas Wildlife Rehabilitation Coalition (TWRC) is fundraising for a new building, which is supposed to include “a dedicated bat room.”

“That would really help with these situations as we continue to see these strange weather patterns come through,” Mary Warwick, HHS TWRC Wildlife Director, said in a video posted to Facebook. She shot the video in her attic, where she housed many of the rescued bats in two dog kennels. “We could really use more space to rehabilitate the bats,” she said.

The Mexican free-tailed bat is the most common kind of bat fluttering around Texas, and is the official “state flying mammal.” They typically spend winters in Mexico, but will migrate North to give birth and raise their young in big “maternity colonies” by early spring. The bats need warm and humid homes for their growing families — usually in caves, but they’ll make do in bridges and tunnels, too.