Concerns about the New World screwworm have put Texas pet adoptions on hold

Concerns over the New World screwworm have halted pet adoptions across Texas, potentially endangering thousands of dogs and cats. This invasive insect, which has crossed the border from Mexico for the first time in 60 years, is spreading across southern Texas and southeastern New Mexico. The screwworm can lay eggs in the wounds or mucous of mammals, leading to flesh-eating larvae.

As a result, forty-four states have restricted pet movements from infested areas, causing overcrowding in state shelters that depend on adoptions. The Gulf Coast Humane Society in Corpus Christi has seen its animal population grow from around 325 to nearly 450 due to restrictions in New York state. Shelters are struggling to find space for transported animals, leading some to euthanize more animals.

Texas has a surplus of adoptable dogs and cats, with nearly 89,000 dogs transferred out of shelters in 2025 alone, and about 45,000 euthanized. The state also leads in cat adoptions and euthanizations, with nearly 53,000 dogs and 29,000 cats transferred out and 29,000 euthanized. The population of stray dogs and cats in Texas is the highest in the nation, with about 439,000 in 2025, due to its large population and warm weather.

Veterinarians and animal welfare advocates attribute the issue to a lack of spaying and neutering among pet owners, particularly in rural areas where dogs are often used for work. The Houston Humane Society, for example, has placed a limit on its animal population of about 200 by utilizing foster homes and helping pet owners keep their animals longer.

The United States Department of Agriculture is working on a $750 million fly factory in southern Texas to combat the screwworm by breeding sterile males to release into the wild.