The big, bad wolf may not be to blame for the drop in elk numbers in Yellowstone National Park.
Michigan Technological University researcher John Vucetich says years of drought and pressure from the elk's primary predator, the human hunter, appear to have had a far greater impact on the region's elk population.
Elk numbers have dropped by over 40 percent in the 10 years since gray wolves were introduced to the park. But a statistical analysis of data from the Yellowstone region shows that drought conditions and hunting pressure alone would be expected to cut in half the number of elk from 1995 to 2005 -- during which time the elk population fell 44 percent, from about 17,000 to 9,500, he said in a report published in Oikos, an international journal of ecological research.
"You don't need wolves in the picture at all to explain the population drop," Vucetich said in a news release.
He's not surprised, however, that many would finger the wolf as the main culprit.
"The belief certainly seems rooted in common sense," he said. "But our work shows that the timing of the elk decline is coincidental with wolf reintroduction and that other factors are to blame."
Copyright 2006 by United Press International
Explore further: Serbs protest moving of famous inventor's ashes