To the casual observer, one wolf might look the same as another but to those in the know, there are crucial differences between the various species of wolf. A recent study, however, suggests eastern and red wolves—previously thought to have different ancestry from other gray wolves—might be hybrids of gray wolves and coyotes. The potential hybrid nature of the wolves could pose a problem for how they are viewed by the Endangered Species Act (1973). It could also be the justification for keeping gray wolves on the protected list.
Setting off the issue is the US Fish and Wildlife Service’s argument recently to consider removing gray wolves from endangered species protection. Gray wolves were hunted almost to extinction and were included under the Endangered Species Act in 1973. Red wolves were also included in the Endangered Species Act in 1973, but eastern wolves are not listed under the protected species. This fall, the Fish and Wildlife Service will make a decision about the continued inclusion of the gray wolf on the protected list.
Researchers from Princeton studied the genomes of a variety of wolves and coyotes. They found that eastern wolves are 3/4 gray wolf and ¼ coyote, while red wolves are a ¼ gray wolf and ¾ coyote. The study, funded by the National Science Foundation and National Institutes of Health, suggests that eastern wolves and red wolves are not separate from gray wolves as previously thought.
The study also casts concern about the Endangered Species Act, which does not protect hybrid species. That’s because when it was passed, interbreeding wasn’t thought to be as common as it is now known to be.
“Our findings demonstrate how a strict designation of a species under the ESA that does not consider genetic admixture can threaten the protection of endangered species,” lead author Bridgett vonHoldt said in a news release.
Gray wolves could be taken off the Endangered Species list simply due to a perceived error in the original listing that stated the gray wolf’s territory included the Great Lakes region and eastern states. When the eastern wolf was thought to be a distinct species and found to occupy those regions, the assumption was an error had been made in the protected species listing, and gray wolves did not occupy that territory. Errors in the listing can result in a species being removed from protected status.
Since researchers now suggest eastern wolves are a hybrid of coyotes and gray wolves, this indicates gray wolves must have roamed in the Great Lakes and eastern states. The original listing, researchers say, is correct and gray wolves should not lose their protection.
Although the results of this study contradict previous studies, the primary issue centers on the lack of protection of hybrid species. The red wolf, previously protected because it was thought to be a different species, could lose its protection. Or, if both the eastern and red hybrids are recognized and protected as gray wolves, their small numbers could help keep the overall gray wolf numbers low, which would ensure the gray wolf remains protected.
But because the Endangered Species Act does not mention hybrid species, it isn’t yet known what will happen to the red or eastern wolf populations. In the meantime, researchers argue the evidence that eastern wolves carry gray wolf genetics should be proof enough to continue protecting gray wolves.