Are Wolves Interbreeding Themselves to Extinction?

By Eliza Strickland | October 16, 2008 4:20 pm

gray wolfA legal battle is raging on over whether gray wolves should be removed from the endangered species list in both the Northern Rockies and the Great Lakes region, with the federal government and environmentalists fighting over whether the wolf populations have recovered. But the situation has been made more complicated by a biological battle over whether the present-day wolves are the same animals, genetically speaking, as the wolves who lived in North American forests hundreds of years ago.

The court cases began when the U.S. Fish and Wildlife Service lifted protections from wolves in the Great Lakes states in 2007, and from wolves in the Rockies earlier this year. Environmental groups contested both decisions. The Great Lakes decision was overturned in September when a judge said the wildlife agency hadn’t followed the law; the Northern Rockies ruling covering the states of Wyoming, Idaho, and Montana was also overturned. After wolves were allowed to be shot on sight across most of Wyoming — and all three states began planning public hunts — U.S. District Judge Donald Molloy in July issued an injunction to block the killings. On Tuesday, Molloy went a step further, restoring the animal’s endangered status [AP]. However, wildlife officials say they’ll try to delist the wolves again in 2009.

The biological complication stems from a genetic study of the Great Lakes wolves conducted by Jennifer Leonard, which showed that these wolves are now genetically distinct from the grey wolves which populated the area before humans cleared the forests. Leonard’s DNA analysis reveals that the wolves have hybridised with coyotes. If wolf-coyote hybridisation in this area follows the same pattern as it has in southern states, grey wolves could be in trouble. “In the southern US, hybridisation is a major threat to the red wolf,” says Leonard. It too is mating with coyotes, and because coyotes outnumber the red wolves, the hybrids are back-crossing with coyotes to the extent that the red wolves could be subsumed into the coyote population [New Scientist]. Leonard sees her findings as an argument for keeping wolves on the endangered species list while more research is done.

But other biologists have found fault with Leonard’s study, and believe that wolf populations are thriving, sustainable, and wolf-like enough to fit the bill. Biologist Tyler Wheeldon recently conducted his own study, and he concludes that the wolf population in the Great Lakes is fairly similar to its make-up in the 1900s, and thus no longer endangered. “Today we have a large top predator which is not coyote-like, which is what they wanted to restore,” says Wheeldon. “If you have a recovered population that is filling the role of the wolf, we shouldn’t worry if it’s exactly what used to be there” [Nature News].

Image: Wikimedia Commons

  • brooks

    so what? the peregrine falcon we have in the US isn’t the “same” bird we used to have. same with the wild turkey. all of the wolves on isle royale have coyote mtDNA.

    but darwinism puts the lie to biological essentialism. *niche* is what is important. function. so does the gubmint want to do “platonic” science? or *real* science?

  • Ken Fischman, Ph.D.

    If you will pardon the mixed metaphors, the controversy over whether wolf/coyote hybrids are really wolves is a red herring. Evolution does not stand still. Species are always changing.

    It is true that wolves do occasionally hybridize with coyotes as well as domestic dogs. That does not make them any less wolves. Few people know that most bison, except for the herds in Yellowstone and Montana, are really bison/cattle hybrids.

    The wolves today in North America are not identical with those that roamed this subcontinent even a few hundred years ago. Of the 23 wolf subspecies taxonomist Edward Goldman identified in 1945, we have lost seven, mostly due to deliberate human actions. We now recognize at least three living subspecies, the “Tundra” and the “Timber” wolves, as well as Canis rufus.

    What is important is that there is once again a large wolf who acts as keystone predator, brought back to a mere 5% of its former range.

    The chance of Canis lupus hybridizing to a significant extent with coyotes is slim. Unlike their much smaller southeastern cousin, the red wolf, Timber wolves usually kill coyotes as well as Canis familiaris whenever they can catch them.

    Animals (and plants) frequently interbreed with close relatives. This is one of the ways evolution works. There is evidence that even Homo sapiens interbred with his kissing cousin, neanderthalis.

  • Ken Fischman, Ph.D.

    this is a test

  • brooks

    that was basically what i said, just with different examples.

  • Linda Rogers

    UM, who cares? Species have been going extinct for billions of years and this ole planet just keeps spinning around. the only people who really give a rat’s patootie are the envirowackos who have more time than sense. It is not necessary to perform wholesale slaughter of course, so the japs and russians should not be allowed to decimate the dolphin and whale populations. But, have some sense, people!

  • Heath

    Maybe there are just too few wolves left for them to find and mate with because stupid “hunters” with too much time on their hands (who shouldn’t be allowed to breed themselves) are killing them to0 quickly.

  • Ed Foster

    Ken, the Neanderthal/Cro Magnon link is pretty well disputed by the DNA work that’s been done up to now, and it doesn’t look all that promising for what’s little is left of the genome to be mapped. They aren’t ancestral to anyone alive today.

    The entire hypothesis was conjured up on the basis of the remains of a single young girl found in Portugal, whose heavy features seemed “Neanderthalish” to wishful thinkers.

    Forensic pathologists and orthopedic surgeons who looked at the remains seem to be in no doubt that her deformities were genetic, presumably engendered or worsened by the desperate inbreeding the dwindling Neanderthal population underwent as they fell back into their last redoubt, the Iberian peninsula.

    As for the wolf/coyote hybrid, it’s the standard predator here in southern New England now. I saw a German Shepard sized bitch cross calmly through 4 lanes of traffic a while back in downtown Bloomfield Connecticut. She knew to wait for the light, or at least understood the timing element of the cars stopping at the light.

    Several males I’ve seen also seem to have standardized at about Shepard size. I would guestimate in the vicinity of 70 to 85 pounds, based on 50 years as a dog breeder and AKC show handler.

    So, no answer, only a question. Is it a big coyote or a small wolf? Either way, it seems to be performing the duties of both, and the spread of the animal has been explosive, fueled by the area’s massive white tail deer population.

    One wonders if the increase in size is due to more wolf genes, or simple selection among less hybridized coywolves for an animal big enough to bring down a deer unaided. I gather they den together but hunt singly due to the semi suburban terrain.

  • http://discovermagazine sam

    the hunters shouldnt be Able to shoot the wolves ..THEN WE WOULDNT HAVE THIS PROBLEM

  • Zac

    Come on people look at the fax! Sooner or later wolves and cyotes will have hybridisation and the genetics of them will fuse in way that we wont be able to tell the 2 apart. Pleaes tell me im not the only one realizes this. Althought im under 13 when i grow up i want to study them as wolves and cyotes not a mix of the 2. And if that happens and they do get to that point of genetics a beautiful creation will be lost forever );


Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!


80beats is DISCOVER's news aggregator, weaving together the choicest tidbits from the best articles covering the day's most compelling topics.

See More

Collapse bottom bar