Armadillos are common in the southern United States, thanks in part to the warmer weather that attracts them, but these creatures have recently begun to make a home for themselves in the Midwest – and during the colder months, too.

According to 101 Highland Lakes, nine-banded armadillos have historically thrived in the Southwest, with Texas having the largest population in the country. However, thousands of miles further north, the armadillo is becoming more common.

Armadillos have been making their way up rivers and streams to the Midwest in recent years, and thousands of them have been spotted as far north as Nebraska, Iowa, and Illinois.

“We’re surprised because we didn’t expect to find them this far north in the winter,” said Dr. Agustin Jiménez, an associate professor of biological sciences at Southern Illinois University, to AccuWeather’s Emmy Victor.

Over the winter, a couple in Illinois sent AccuWeather a video of an armadillo in their backyard, and just two weeks later, another armadillo was spotted in Illinois. The precise reason for these animals migrating north is unknown, but several studies have linked it to climate change and warmer winters.

“Normally, the temperatures of the winters that we would expect for this area would have taken care of them. They wouldn’t make it. They are, however, surviving “Jiménez stated.

According to a study published in the Wiley Journal of Biogeography, warmer winters may one day allow armadillos to live as far north as Pennsylvania.

“Armadillos could potentially be found in areas that were completely unexpected 20 years ago,” Colleen McDonough, an ecologist and armadillo expert at Georgia’s Valdosta State University, told National Geographic.

Jiménez’s students recently installed a tracker on armadillos found in southern Illinois to track their movements and learn more about why they migrate north. The results showed that the armadillos are staying close to home, and more could be seen in southern Illinois.

Because the southern part of Illinois has a milder winter than the rest of the state, Jiménez said he doesn’t expect them to live much further north.

“It may make it difficult for them to reach larva, the insects on which they feed. Currently, the winters and ground conditions in southern Illinois make it easier for them to access some of these insects “Jiménez stated.

The Illinois Department of Natural Resources asked the public to report any sightings in the state in February 2022. According to the Chicago Tribune, over 400 reports were received in just 24 hours, with the majority coming from the state’s southern region.

However, armadillos have been spotted in central and northern Illinois. An armadillo was discovered dead behind a Kia dealership in Springfield, Illinois, in the summer of 2021. Two reports were received in Cook County, which includes Chicago, in the northern part of the state. This county has received two credible reports of armadillos in the last 30 years.

Armadillos have also been spotted outside of the Midwest, including in Virginia and North Carolina, where officials are asking residents to report any sightings. Reporting sightings will assist officials in monitoring and understanding the animals’ newly expanded territories.

Armadillos have been steadily migrating northward over the last century. These animals originally crossed the Rio Grande River in the 1850s then the Mississippi River in the 1930s. By the 1990s, Armadillos began making appearances in Tennessee, North Carolina and Virginia, according to National Geographic.