Discovery sheds light on wolf dispersal, recolonization of Rockies
Kent Laudon, a wolf management specialist for Montana Fish, Wildlife and Parks, which assumed wolf management from the federal government three years ago, recently recovered a radio collar that had been affixed to a 2-year-old male gray wolf more than 15 years ago. The collar was lying on the ground in a remote drainage of British Columbia’s North Fork, about 62 miles from where researchers captured the wolf in 1999.
Deployed by Tom Meier and Diane Boyd of the U.S. Fish and Wildlife Service’s wolf recovery team, the radio collar was attached to wolf 4387, who belonged to the South Camas pack in the North Fork Flathead drainage.
He was tracked with the pack through March of 2000, when he disappeared, and the collar was recently discovered 61.8 miles from his capture location. It looked as though it may have been chewed off, Laudon said – sometimes wolves will help divest one another of the nuisances – though he can’t be sure.
While Laudon doesn’t know with any degree of certainty what the wolf was doing so far from home, he said it’s likely the wolf set out to begin his own pack, or join another, as a disperser. Wolf dispersal has been a critical behavior in maintaining the genetic diversity of a pack because it keeps incest rates down, helps balance the wolf-to-ungulate ratio of a population niche, and also reveals how effective they are at breeding and expanding populations geographically. “Incest rates are very low among wolf populations. Sometimes the critters themselves seem to understand relatedness,” he said. “It’s almost like the genes themselves have this instinct. Somehow wolves just know, and dispersal helps a pack maintains itself with the right amount of wolves for a given area.”
Wolves seem to understand when a pack has reached a tipping point, and if the pack isn’t providing enough food for all of its members, certain wolves will peel off and travel long distances to find another pack or breeding female. “The theory is that they leave for breeding rights,” Laudon said. “Wolves can be long-distance dispersers, so they can literally go hundreds of miles when they leave their pack. They can go very far, very quickly.”
Some animals are more submissive than others and seem happy to stay with a single pack forever, but others either have alpha personalities that make them predisposed to become breeders, or they have been ostracized due to inner-pack strife. “It delves into the aspect of biology that really gets inside their heads,” Laudon said. “They have unique and different personalities, just like dogs.”
Gray wolves were eradicated from Montana in the 1930s and the adjacent Canadian Rockies by the 1950s, but recolonized the areas in the 1980s. Between 1979 and 1997, researchers documented 31 of 58 collared wolves that dispersed, leaving their natal home range after separating from the pack. “Wolves seem like they are pretty good at finding each other,” Laudon said. “When I took over there were about 12 packs in Northwest Montana in FWP Region One and Glacier National Park, and last year I documented 64 packs. And they all came from somewhere.”
The Montana wolf population has steadily increased since 2005. Minimum wolf counts are conducted every year and approximately 627 were recorded at the end of 2013. The growth of the gray wolf population, from an extirpated animal, to endangered, to its delisting in 2011, has been a polarizing topic.
The 1995 reintroduction of wolves into Yellowstone National Park made national headlines, and was met with contention from hunters and farmers concerned for their livestock as well as biologists concerned about the introduction of wolves into areas already inhabited by other wolves.
According to Laudon, Canadian gray wolves began ranging into the United States in the late ’70s. In 1986, the first wolf den in the western United States in more than 50 years was documented in Glacier National Park. But none of the wolves in Northwest Montana were introduced and, as Laudon points out, “they had to come from somewhere.” “Any time we find a missing wolf from somewhere else, we assume dispersal data. It’s an important thing to understand that phenomena, and we certainly do understand it better now,” Laudon said.
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