Predation on young elk by wolves tends to come during the winter months when deep snow and cold weaken the animals,,,,,With last years mild Winter in the Bitteroot Mountains of Montana, Elk were able to fare well in their age old dance with Wolves............Pumas continue to be the key predator of Elk during the Spring and Summer "pulse" when Elk calves come into the population......U. of Montana and Montana Fish, Wildlife & Parks researchers will continue their three year study of Elk and the predators that hunt them during the upcoming Winter months to see if these predator/prey dynamics hold up

Numbers look good for East Fork Bitterroot elk herd; lions biggest threat

  By PERRY BACKUS Ravalli Republic

HAMILTON - The elk herd in the East Fork of the Bitterroot may be on the rebound.Montana Fish, Wildlife and Parks biologist Craig Jourdonnais counted 56 elk calves per 100 cows during his July aerial flight over the area.There has only been one other time since those flights began in 1976 when elk calf numbers were so high.

"It was the first bright light that we've had for a while," Jourdonnais said. "It is a big deal."
The elk herd in the southern reaches of the Bitterroot Valley has been struggling for several years. At one point, that ratio between elk calves and cows dropped into the teens in the East Fork. In the West Fork, the numbers were even worse.

Elk

A kind winter and last summer's ample moisture and lush vegetation are probably the chief reasons for this year's jump in elk calf survival."We're also putting a little more hunting pressure on lions, bears and wolves," Jourdonnais said. "That's helping these elk bounce back too."

Researchers taking part in a three-year elk/predator study in the southern Bitterroot have noticed a decline in the number of elk calves killed by predators through the month of July.
University of Montana assistant wildlife biology program professor Mark Hebblewhite is the co-leader of the Bitterroot elk study that equipped 76 elk calves with radio ear tags this spring.
After the initial pulse of mortality following the June birthing season, Hebblewhite said the tagged elk calves have been faring well.

Gray Wolf

"Once the elk calves got up and moving, it really slowed down for us," Hebblewhite said. "There's not been a lot of mortality after that initial pulse."Like last year, mountain lions have been responsible for most of the elk calf mortality.Of the 17 elk calf deaths since June, six were killed by lions, four from black bears, two were human related, including one caught in a fence, and researchers couldn't tell for sure how the remaining five died.

"Compared to last summer, the numbers were pretty similar," Hebblewhite said. "We wondered if we would see a different pattern of predators, but it's stayed pretty consistent to last year."
So far this year, the research team has documented twice as much lion-caused mortality in the West Fork of the Bitterroot. Four elk calves were killed by lions there and two died in the East Fork.
"The picture that's emerging so far is that our local elk population in the Bitterroot is similar to the Blue Mountains of Oregon and Washington where lions are driving the population," he said.
Predation on young elk by wolves tends to come during the winter months, but FWP research technician Ben Jimenez said last year's uptick in wolf activity wasn't as high as people expected to see.

Puma

"It was a screwy winter with not a lot of snow," he said. "That's why we do these studies for three years. ... Who knows? Maybe this winter we'll see a huge number of wolf kills."Jimenez and other researchers try to get to the sites where calves have been killed as quickly as possible after the radio signals a mortality.If they can get there quick enough, the clues left behind by the predator will tell them what kind of animal was responsible for the death.

A mountain lion's trademark is deep bites on the neck and jaw or claw marks along the body of the prey. A lion will pluck all the hair away from around the ribcage before it begins to feed.
"It looks like they've shaved it with clippers," Jimenez said.Both lions and bears tend to cache whatever they don't eat, but a lion is more fastidious about covering its prey."Bears are not usually as neat," he said. "They tend to kill things with more massive blows. Bears crush things."
A wolf kill site is something totally different."Oftentimes it looks like a bomb went off," Jimenez said. "You'll find multiple places where the animal went down and then got back up."A wolf pack will leave bones and other material scattered over a much larger area. They also tend to leave lots of tracks and scat too.

Griz

"You definitely get honed in on some this stuff after doing this for a while," he said. "You pick up on the little things. We are trying to be very careful on deciding the cause of death. We really attempt to make as few assumptions as possible."

Like last year, the researchers are having problems keeping the radio ear tags on elk calves. Unlike last year, when the tags simply fell off, this year the tags are breaking.So far, the study has lost 18 tags to the defect."It's just infuriating," Hebblewhite said. "But it's not lethal to the project by any stretch of the imagination."The researchers will capture and tag another contingent of calves that will be followed through the winter months.

Jourdonnais is hopeful the upward population trend will continue.When he arrived in the valley in 2009, the elk calf/cow ratio through the Bitterroot was about 15 calves per 100 cows.
"Back then, we didn't know how this was going to go," he said. "This is a great start. We're very cautious and hopeful that if it goes the way we have it designed in management, some of the hunting restrictions could be lifted in the next biennium."

In the next few years, the hope is hunting will return to a general season for bull elk and some antlerless opportunities in the East Fork, Jourdonnais said.
"I think it's going to be a long hard road to get antlerless opportunities back to HD 250," he said.