MARK GOCKE / WYOMING GAME AND FISH DEPARTMENT
Ken Mills, a Wyoming Game and Fish biologist, inspects a wolf from the Lava Mountain Pack in 2014.
Mike Koshmrl | jhnewsandguide.com
The largest wolf pack known to exist in the American West roams the Gros Ventre hill country about 30 miles northeast of Jackson.
At last count there were 24 members of the Lava Mountain Pack, U.S. Fish and Wildlife Service annual monitoring reports show. While far from unprecedented historically, a wolf pack two dozen strong has nine more members than any other pack surveyed this year in Wyoming, Montana, Idaho, Washington or Oregon, state and federal reports indicate.
“That’s a very large pack,” said Mike Jimenez, the service’s Northern Rocky Mountain wolf coordinator. “They actually had a double litter a year ago, and that’s uncommon.”
First documented in 2008, the Lava Mountain Pack ranges deep in the Gros Ventre north of the river’s main stem. It was already the largest pack in Wyoming a year ago when it had 15 wolves. Then its members added the two litters of pups in 2014, Jimenez said.
History suggests that the days of the Lava Mountain Pack’s jumbo size are likely numbered, he said.
Six years ago the largest gang of wolves in Wyoming was the Buffalo Pack, which roamed the Mount Leidy Highlands in numbers as high as 22.
The next year the pack fell to 14 members.
“After that they split up, and the pack was gone,” Jimenez said.
“Big packs don’t stay big for very long,” he said. “What happens is they kick out dispersers, or they fracture.”
Large carnivore biologist Ken Mills of the Wyoming Game and Fish Department also said the Lava Mountain Pack would more likely decline than persist for years at such numbers.
“They don’t tend to be very stable, just because they are so large and they require a lot of resources,” Mills said. “Socially they don’t tend to be stable.”
Before a judge’s September court ruling, Mills was the biologist who managed Wyoming’s wolf program. About a year ago he came face to face with the Lava Mountain Pack when he collared members for a research project on wolf predation in the Upper Gros Ventre. The research was put on hold after tracking collars failed and management jurisdiction shifted to the federal government.
Since the ruling, the U.S. Fish and Wildlife Service has resumed management and hunting has been barred. Because they live within Wyoming’s trophy game area, the Lava Mountain Pack was never subjected to legal hunting last year.
It’s usually in protected areas — where human-caused mortality is low — that very large wolf packs tend to develop, Jimenez said.
Since the reintroduction of wolves to the West two decades ago, the largest pack has proved to be Yellowstone National Park’s now-defunct Druid Pack.
“Just think, in Yellowstone there’s no public hunting, no livestock control,” Jimenez said. “It’s pretty much running in a natural state.”
The Druids, which peaked at 37 wolves in 2001, declined naturally and broke up altogether by 2010.
It was a similar story for other Yellowstone packs with 20-plus wolves, such as the Nez Perce and Swan Lake packs, Jimenez said. They swelled in size after reintroduction and then declined and eventually disappeared, he said.
“The size of the big, big packs, it isn’t inherently better,” Jimenez said. “You get a pack that big, and you can imagine it’s probably formidable and it’s a pretty good defender of its territory.”
But an abundance of prey needs to be present to sustain very large numbers of wolves, he said.
The Upper Gros Ventre, Mills said, is a “rich environment without a lot of livestock.”
Last year, reports show, the Lava Mountain Pack killed two cattle. Generally, Jimenez said, “They’re not a particularly problematic pack.
“They’ve exploited the situation there,” he said, “and they’ve done very well.”
Wolf numbers in the Jackson Hole area as a whole were relatively stable over the past year.
Other Gros Ventre packs tended to stay the same size or shrink.
The Blackrock wolves, with territory to the west of the Lava Mountain Pack, stayed steady at four members. The Pinnacle Peak pack, a frequenter of the National Elk Refuge and Lower Gros Ventre, didn’t budge in number and came in at the second largest in the region with a dozen wolves, Fish and Wildlife’s report shows.
The Lower Slide Lake and Lower Gros Ventre packs both stayed small, numbering four animals or less.
Phantom Springs wolves, residents of Grand Teton National Park and the Buffalo Valley, decreased from 11 to five wolves.
The park’s northern Huckleberry Pack also decreased significantly — from 11 to three wolves.
The Pacific Creek Pack, inhabitants of the Teton Wilderness, were stable over the past year and remained at six members.
Wolves in the southern extent of Jackson Hole and in the Hoback River drainage fared well. The Hoback-area Horse Creek Pack increased from five to eight. A new group of eight wolves, the Dell Creek Pack, sprung up in the area north and east of Bondurant, reports show.
