Arnulfo Moreno-Valdez, director of the Natural Museum of Tamaulipas in Mexico, displays a vampire bat. (Photo by Arnulfo Moreno-Valdez)
By JAYME BLASCHKE
University News Service
Texans are used to putting up with the consequences of notoriously hot summers, but if researchers’ predictions are correct, then record drought and wildfires won’t be the only hazards residents of the Lone Star State will have to contend with in the future.
Vampire bats may be on the way.
Once only seen in the U.S. in horror films, vampire bats are expanding their range in Mexico as a result of climate change, and computer models indicate they could become year-round Texas residents within 50 years. For Ivan Castro-Arellano, a biologist and wildlife disease expert in the Department of Biology at Texas State University-San Marcos, the concern is that Texas’ increasingly warmer winters might allow the damaging pest to expand into the state well ahead of schedule. Castro-Arellano is one of more than 40 scientists throughout the Texas State University System working through the Institute for the Study of Invasive Species in Huntsville to study and develop strategies to deal with invasive species across the state.
“They will not survive in places that go below 10 degrees Celsius (50° Fahrenheit) for a sustained period of time. Models predict those minimum temperatures are going to rise from where they are now. If that happens, obviously they are going to advance,” Castro-Arellano said. “However, there are many ways the animals may escape that restriction. The models are an oversimplification, because if the animals can find a place to roost during the day that keeps them warmer than that 50 degree limit, then they will be able to exploit new areas, especially in Texas.”
The warming trend in Texas is reflected in the recently-updated USDA plant hardiness zone map, which generally revised minimum winter temperatures upwards 5°F across the state.
That climate shift pushes the Lone Star State one step closer to becoming suitable habitat for vampire bats.
While native Texas bats are beneficial, eating tons of insects that would otherwise damage crops that make up a large part of the state’s agricultural industry, vampire bats could pose a big threat to livestock. The bats target cattle and other livestock, approaching the animal on the ground and licking it with anesthetic saliva that also prevents blood from clotting.
Then it bites the victim with razor-sharp teeth and laps up the free-flowing blood. Since they feed on mammals, they can easily spread rabies and infect herds of domestic livestock. They also tend to target the same victim night after night, and repeated feedings can kill individual animals. Vampire bats cost ranchers in Mexico millions of dollars each year in losses.
