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Nighttime cameras reveal lives of mountain lions
Motion-triggered video cameras left at wildlife kill sites gives researchers unprecedented opportunities to observe the habits and behavior of mountain lions. File photo

Nighttime cameras reveal lives of mountain lions

Apr 28, 2013 - Mike Koshmrl, For the Associated Press

JACKSON -- Mark Elbroch always knows what his cats are up to.

When the mountain lions Elbroch and fellow researchers are tracking make a kill, the Teton Cougar Project pays a visit.

At the carcasses, they leave behind a video camera activated by a motion-sensitive trigger.

The high-definition feed it picks up tells a story.

"I've been studying mountain lions for 12 years," Elbroch said, sitting before his computer in his Kelly office. "I've learned more from videos in the last year than I could ever have imagined.

"We're seeing the secret lives of cats," he said, "in the most real sense."

On April 10, Elbroch headed out to check on the remains of a 2-year-old bull elk that recently had been downed by F51, a female mountain lion he's been tracking.

Data from collar

In the field, GPS data from her radio collar told him that she had been spending her day bedding, along with her lone cub, in the hillsides just hundreds of yards away from where he stood.

Last year, about two miles away, F51 gave birth to three kittens. Using the GPS data, Elbroch visited the den to verify their numbers.

This winter GPS coordinates led him to two of them again. This time he found just carcasses, the casualties of run-ins with wolves.

At the elk carcass, cached a stone's throw from a road in the Gros Ventre hills, Elbroch retrieved the cameras.

The body of the bull was blanketed in elk hair and debris deposited by F51. The lioness' ploy has worked so far: Video shows scavengers hadn't yet found the carcass.

Mother and cub

Back at his office, Elbroch reviewed what F51 and her cub were up to last night. At 8:50 p.m. -- after darkness had set in -- she padded into the view of the Sony camcorder and infrared light. She got to feeding. Shortly thereafter, the cub hunkered down by her side.

After watching the videos almost daily, Elbroch has developed a feel for the idiosyncrasies of individual cats.

"They are a hysterical couple," he said of F51 and the cub. "(The cub) spends half her time stalking mom and tackling her."

The Teton Cougar Project, now a dozen years old, was founded by Howard Quigley and Derek Craighead. The biologists sought to understand cougar movements, population dynamics, predator-prey relationships and the cats' interactions with other large predators, including wolves, grizzly bears and black bears.

Population shrinking

The group's findings are beginning to hit the presses. In the coming year, Elbroch, fellow Cougar Project biologist Patrick Lendrum and others plan to publish three papers.

The first, which measures the effects of wolves on the cougar population, turned up perhaps the most shocking results: The population, they found, has fallen by half since the project started.

About 18 adult mountain lions are now thought to inhabit Jackson Hole, Elbroch said, along with an equal number of cubs and "dispersers."

"Wolves appear to be knocking them back," Elbroch said. "And they seem to be targeting kittens."

Competition, not predation, is the driving factor.

"We sometimes find (cubs) torn up to pieces," he said.

Watching archived videos later, Elbroch narrated a segment showing a wolf pushing M68, a male lion, off of a carcass.

"You can see that (the wolf) doesn't care at all about the carcass," Elbroch said as the wolf sniffs around. "He's just looking for the cat. He doesn't care at all. Where's the cat?"

The Teton Cougar Project has been evolving. Last year it separated from Craighead Beringia South, latching onto Panthera, an international big cat conservation group.

The project was down to one collared cat early last year, but Elbroch, Lendrum and volunteers helped boost that number to 15. Four of those were recently killed -- three by wolves -- leaving the research group with 11 collared animals.

Cougar vs. fox

Much of Elbroch's work of late has been delving into what becomes of ungulate carcasses after cougars take them down. A better understanding of the behaviors of scavengers has been a by-product of the research.

"We go through and catalog all this stuff," he said. "We figure out when what species are there, the hierarchy of the scavengers, who pushes off who. All that stuff is fascinating."

Some of the scavenger behavior he has noted has never been witnessed. Foxes, in particular, have perplexed the cougar biologist.

"We've seen some crazy exchanges," Elbroch said of competing red foxes.

"You'll get these dominance displays where one will race backwards, running backwards, with its tail to the side shooting (excrement) at the other one. We've now seen it three times. It's the most bizarre thing we've ever seen. And we have no idea what's going on."

After leaving the elk carcass, Elbroch headed into Grand Teton National Park.

He postholed through snow on steep banks leading to a video camera set up on a moose calf a male lion had killed along the Snake River below Teton Point Overlook.

It's the first moose a research cat has killed in two years. M29, an adult male, did the deed.

The moose, strewn about, has been "inactive" -- meaning the cougar moved on -- for nearly a week. Lower portions of the calf's legs remain, but its head and almost all the meat had been consumed.

Walking a circle around the remains, Elbroch searched for the head, which has disappeared since his visit there the week before.

"You can see there's not much to go on," Elbroch said.

The head didn't turn up, but Elbroch stumbled upon a mountain lion "toilet."

"This is part of the kill," he said, kicking into a sizeable pile of leaves, sticks and dirt. "They are fastidious about covering stuff at times."

Marrow sampling

Back at the moose calf carcass, Elbroch collected his cameras for the last time and took bone samples from an intact section of femur.

The health of an animal can be determined by its marrow.

"The fattier the animal, the healthier the animal," he said after sawing into the bone. A fatty bone marrow sample would be completely white -- it would be like wax, you could cut it like cake. The fact that this is completely jelly is a sign of unhealth. This was not a healthy calf."

Just before trekking back up to the Teton Point Overlook parking lot, Elbroch's sees an inquisitive pine marten perched low on a conifer not 50 feet away.

"We constantly get these guys at kills," Elbroch said, chirping to draw the inquisitive mustelid nearer. "He's been no doubt nibbling."

The curious marten, a large male, cautiously proceeds, bounding up the tree even closer. It grabs something and begins chewing. "That's a chunk of moose!" Elbroch says. "He stashed a piece of moose up there, that little bugger."

The moose may have been "inactive," but only to the cougar.

___

Editor's note: Mike Koshmrl writes for the Jackson Hole News & Guide

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