Out for a swim: Grizzly conquers lake
Could it be webbed claws? Or maybe an ancient connection to a Labrador bloodline?
In any case, a young grizzly bear has demonstrated Olympian swimming skills on Flathead Lake, proved with GPS data from a satellite collar that was recovered Monday near the town of Swan Lake.
The 4-year-old female was trapped in June 2010 as a management bear because of her proximity to the Flathead Lake Lutheran Camp south of Lakeside. It was an unusual place for her to show up, well outside established grizzly bear habitat.
“We thought that because we don’t have bears very often on the west side of the lake that we would put a collar on her,” said Rick Mace, a research biologist with Montana Fish, Wildlife and Parks in Kalispell.
A decision was also made to relocate her to a remote area near Blacktail Mountain west of Lakeside, because after all, that was an area she naturally migrated to.
It didn’t take long for the bear to make her way back to the lake, this time wandering south to the Rollins area.
“She spent most of 2010 on that side and then during Labor Day weekend of last year is when she started her aquatic activities,” Mace said.
Aquatic activities, indeed.
The bear swam from Painted Rocks point to Cedar Island, where she spent a day. Then she swam about 3 miles southwest to Wild Horse Island, where she wandered around for three days before swimming south about a mile to the foothills northwest of Polson Bay. After several days there, she embarked on a crossing to Flathead Lake’s east shore.
“She spent a minimum of eight hours in the water swimming [during that crossing], probably closer to 12 hours if you put it all together,” said Mace, who calculated the bear’s time in the water from coordinates recorded in four-hour intervals on the satellite collar.
The total crossing spanned about 7 miles, but the bear got a fortunate one-day layover on tiny Bird Island before forging on just north of Skidoo Bay and finally reaching the east shore on Sept. 7. From there, she moved east into the Mission Mountain Range, denning up on Kelly Mountain, which overlooks Swan Lake.
“She’s kind of settled down there, sort of a Swan Lake bear now,” Mace said.
The bear’s satellite collar was set to automatically release, and when it did, Mace’s research assistant, Lori Roberts, was able to recover it after a 15-minute walk from a road in the Swan Lake area. While the bear’s location could be monitored from satellite about once a week while the collar was on, the complete information on her movements had to be downloaded from the collar after it was retrieved.
Mace knew the bear had gotten to the Swan Lake area, but he didn’t know exactly how, and he was somewhat surprised at how much she swam.
“This one stands out,” he said. “Every bear is kind of cool when you look at the nooks and crannies where they’ve gone, but this is the first one that’s done something like this.”
Mace is aware of grizzly bears, mostly males who have larger home ranges, making crossings on Hungry Horse Reservoir or on Lake McDonald, but nothing approaching the distances this bear swam on Flathead Lake.
“We don’t have a lot of huge lakes within occupied grizzly habitat,” he said. “Flathead Lake, I think, would be right up there just in terms of the sheer time she spent in the water.”
Mace calculated that the bear traveled 1,200 miles on land and water while she was wearing the collar from June 2010 to September 2011.
But she did quite a bit of traveling before that. She was captured as a yearling cub along with a male sibling and her mother in the Foothills Road area in May 2009. The bears were tagged with microchips and relocated to the Spotted Bear area east of the Swan Mountains.
So somehow she managed to make her way to the west side of Flathead Lake.
“We don’t know if she swam over there or walked around” the lake, Mace said. “Compared to a lot of the other females we follow, she has quite a large home range, but the fact that she has Flathead Lake in the middle of it makes it a lot bigger by necessity.”