Three Lone Wolves Left on Isle Royale
There are only three wolves left in Michigan's Isle Royale National Park, making scientists concerned for the survival of this lone group, new research finds.
As part of the annual Winter Study, researchers from Michigan Technological University spotted nine wolves in the area last winter, making this recent sighting an unprecedented low.
"There is now a good chance that it is too late to conduct genetic rescue," John Vucetich, an associate professor of wildlife ecology who co-led the study, said in a statement.
The group is most likely made up of two adults and one nine-month-old pup, possibly the adult pair's offspring. But unlike its pack mates, the pup does not appear healthy. It has a constricted waistline, hunched posture and seems to have a deformed tail, researchers say.
"Those observations suggest that the pup is not well off," added Vucetich, noting that on the study's final day the pup was not seen. "It would not be surprising if the pup was dead a year from today."
But even if the pup were healthy, three isn't exactly a crowd. With numbers this low, the chances that the population will recover naturally are slim to none.
Since 2009, wolf numbers on Isle Royale have plummeted by 88 percent from 24 to three wolves, likely because of inbreeding, which has greatly impacted the packs over the past half century. And without new genetic material thrown into the mix, geneticists fear that this lone group will not ever fully recover.
Though, last April the Isle Royale National Park did say that "there is still a chance of nature replenishing the gene pool as wolves are able to move to and from the island when ice bridges form."
With that in mind, even if the surviving adults are a mating pair, their offspring probably would not fair well. While the researchers are waiting on genetic tests to confirm the wolves' identities and which pack they came from, their best guess is that they are the alpha pair from West Pack. And, as a mating pair, neither is likely to be interested in other potential mates introduced for genetic rescue. (Scroll to read on...)
Although, that doesn't mean scientists have given up hope that visiting wolves could possibly save the Isle Royale population. In fact, during the study researchers observed two visiting wolves, which came and then left across an ice bridge from the US-Canadian mainland. One wolf appeared light-colored, which is uncharacteristic of Isle Royale wolves, and the other was radio collared.
But they didn't stay long. Within the week, the wolves left, possibly not even noticing the three Isle Royale wolves.
Scientists say that the only hope these lone wolves have is to mate with wolves that are reintroduced to the island, or to reproduce naturally.
"One must use the word, 'naturally', carefully these days," noted co-lead author Rolf Peterson, a research professor at Michigan Tech. "The human imprint is written all over the dynamics of this wolf population in recent decades."
It is no secret that humans have greatly contributed to the decline of wolf populations not just in Michigan's Isle Royale National Park, but across the United States.
Due to hunting by humans, gray wolves were nearly wiped out from western states in the last century. There are now an estimated 7,000-11,200 gray wolves in Alaska, 3,700 in the Great Lakes region and 1,675 in the Northern Rockies, according to Defenders of Wildlife.
The IUCN Red List of Threatened Species currently lists the gray wolf (Canis lupus) as "least concern," but there has been some debate recently as to whether the species should be added to the federal Endangered Species List.
As for the Isle Royale population, whether or not humans will take action to help these lone wolves recover remains to be seen.
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