As more and more wolves were killed, those remaining began mating with coyotes. Their offspring were healthy, but crossbreeds. These crossbreeds then mated with coyotes as well, and so did their offspring and on and on. With each passing generation, the red wolf became more like coyotes and less like their own species.

When scientists finally realized that the hybridization of red wolves and coyotes was taking place, there were very few true blooded red wolves left. Those that were found were taken to zoos and bred, but by then, no wild red wolves could be found. Some zoo-bred pups were returned to the wild, where no coyotes lived. Now, a few red wolves are again running free in the wilderness.