Saturday, April 04, 2009

Isle Royale

Ever since I visited this island in the middle of Lake Superior when I was a kid, I've loved the story of the constant struggle between the islands populations of moose and wolves.

However, a recent examination of the islands wolves reveals some problems. They are suffering from backbone malformation problems due to the decades long inbreeding of the tiny colony.
Scientists had long watched for problems from inbreeding, such as poor survival rates for pups. Instead, the first solid evidence surfaced when Jannikke Raikkonen of the Swedish Museum of National History, an expert in wolf anatomy, visited Isle Royale several years ago to examine the project's bone collection.

She identified malformed vertebrae in all wolf remains found the previous dozen years. Such abnormalities show up in just 1 percent of observed populations that are not inbred.
The question now is ... do they introduce outside wolves to "save" the colony?
Historically, biologists have taken a hands-off posture as wolf and moose numbers have risen and fallen, preferring to let nature take its course even if it meant extinction of one or both species. But strong arguments could be made for intervening as well, project leaders now say.
So what are some of the things to consider pro/con in this situation?
The question involves competing scientific and ethical values, Vucetich said.

Opponents of intervention believe humans should not tinker with wilderness systems. Even if Isle Royale's wolves die out, their loss would provide information that could save endangered species elsewhere.

Other would counter that attempting to save the wolves also could yield valuable data, while sparing individual animals from painful bone deformities.

"We have an incomplete understanding of genetic rescue — when and how and why it works," Vucetich said. "Even so, it may be an important conservation tool as more population species become rare."
What do others think?


Mad Hatter said...

Hmm...tough question. How divergent genetically are the island wolves from the closest non-island wolves? It would be incredibly sad to let them die out, but previous human attempts at mucking with nature have not always had the intended consequences (my favorite failure story being the attempted use of myxoma virus in Australia to control rabbit populations)....

Tom said...

I don't know how divergent genetically they are, but considering that they've been cut off from the rest of the world for about 50 years (probably equates to at a minimum 10 generations of inbreeding) any introduction of outside genetic material would be welcomed.

Of course, how the new wolves would respond is anybody's guess ... and if they brought any pathogens with them that the island colonies were not exposed to, or had lost protection against over time, could be more damaging than helpful.