There is only one "true" wolf species in the North and it is the gray wolf (Canis lupus), according to new research.
After analyzing the genetic ancestry of wolves in North America, a team of scientists from New Jersey and California have found that the western wolf is the only genetically purebred species in the continent.
In fact, the remaining wolves — including the red wolf and Eastern wolf — are hybrids with a mix of coyote and gray wolf DNA, and are not evolutionary distinct, the group's study concluded.
However, the report highlights a fundamental problem in wildlife conservation: under the Endangered Species Act (ESA), how should threatened animal hybrids be addressed? And should gray wolves be removed under protection?
Wildlife Conservation For Wolves
Populations of gray wolves once flourished across much of the United States, until the animals were hunted down to near extinction in the late 19th and early 20th century.
In the 1970s, the U.S. Fish and Wildlife Service (USFWS) listed the gray wolf as a threatened species under the Endangered Species Act. This was done because the animal's geographic range once encompassed the Great Lakes region and 29 eastern states.
Researchers from Princeton University and University of California, Los Angeles (UCLA) say the populations of gray wolf species have since rebounded thanks to reintroduction, protections and natural repopulation. This made the wolf recovery in the U.S. one of the most successful under the ESA.
Along with the gray wolf, the red wolf species is also under the ESA protection, but the Eastern wolf is not.
Authors of the new study say the USFWS will decide this fall whether to remove the gray wolf under protection of the ESA.
This proposal has drawn attention to the discord between ranchers, conservationists, hunters and other people who see the predator either as a danger or as part of a rather healthy ecosystem.
The agency says the gray wolf should be removed from the list because the supposed distinct species of eastern wolf lived in the eastern states and the Great Lakes region.
The presence of the eastern wolf in the eastern U.S. would also mean that the gray wolf's original listing could be annulled, they say.
No Distinct Evolutionary Line
In the new study, researchers examined the complete genomes of 12 pure gray wolves, three pure coyotes, six eastern wolves and three red wolves.
The pure gray wolves were taken from areas with no coyotes; the pure coyotes were taken from areas without gray wolves; and the eastern wolves were taken from the Great Lakes region.
In the end, scientists found that the red wolves and eastern wolves were not evolutionary distinct species but were the result of recent interbreeding.
In fact, eastern wolves had 25 percent coyote DNA and 75 percent gray wolf DNA, while red wolves contained 75 percent coyote DNA and 25 percent gray wolf DNA.
"These results suggest that arguments for delisting the gray wolf are not valid," says Princeton Assistant Professor Bridgett vonHoldt, the report's lead author.
Furthermore, VonHoldt and her colleagues suggest that the Endangered Species Act should also cover endangered hybrid species because interbreeding is common in the wild and is not harmful.
Full details of the new report are published in the journal Science Advances.
Photo: USFWS - Pacific Region | Flickr