Scientists studying wild cougars, also known as mountain lions, in northwest Wyoming have been given a glimpse into the secret, snuggling social lives of the big cats’ families.
A recent den study conducted by Panthera’s Teton Cougar Project analyzed the comings and goings of hard-working and affectionate mountain lion mothers using motion-triggered video cameras and collars that track the cats’ location using GPS. They learned new details about kittens’ lives inside the den and how intensely their mothers care for them. Scientists hope the insights—and awwww-inspiring video clips—might help protect vulnerable kittens from hunting.
Mountain lions are also called cougars, pumas, and catamounts—these all refer to the same cat species, Puma concolor. Based on the study’s observations, after giving birth, a typical mountain lion mother stays tucked into her den with her litter of up to five kittens for their first ten days. She purrs almost constantly to communicate with her babies, whose eyes open at about a week old. (See more video from inside a mountain lion family.)
During the next month and a half or so, she occasionally leaves to hunt for herself and might not come back for a few days at a time. A secure den, perhaps beneath the nearly impenetrable underbrush around a fallen fir tree, hides her fragile kittens from predators such as bears and wolves until she returns.
But whether or not she returns is always an “if.” Hunting season in Wyoming starts each year on October 1. At that time, mountain lion kittens might be a few days old or already traveling with their mothers. (Related: "Once Thought Loners, Cougars Revealed to Have Rich Society.")
If a mother mountain lion doesn’t come back after she hunts, “the kittens are doomed,” says Mark Elbroch, Puma Program Director for Panthera, the global wild cat conservation organization.
The study found that when the spotted, sharp-toothed kittens are about six weeks old, the family leaves the den together. The kittens follow their mother, struggling to keep up at first, while she hunts. She often stashes them near a kill site to hunt alone. Once they can keep up, they stay together most of the time.
Humans are almost always the primary cause of death for mountain lions in areas where the two overlap, says biologist Michelle Peziol, who worked with the Teton Cougar Project for five years and is now a graduate student studying the species. (Watch: Cougar Comes Face to Face With Hikers.)
Mountain lion hunting is legal across much of the species’ range, which spans 28 countries from southern Alaska in the United States to Chile’s southern tip, according to Panthera. While it’s almost always illegal to kill females with dependent young, Panthera says it can be difficult for a hunter to know if a female has young. According to the Wyoming Game and Fish Department, more than 70 kittens are orphaned in the state each year due to hunting.
“This is the reality for mountain lions in the western United States,” Elbroch says. “Most are hunted legally and in some states hunted very hard.”
Even older kittens can be doomed if they’re orphaned. Peziol recalls monitoring the status of two kittens whose mother was killed when they were five months old. Lacking mature teeth and hunting skills, they struggled to survive. One starved to death. The other, malnourished, died a few months later from injuries suffered during a botched porcupine hunt.
Watching them try to survive without their mother was “not pretty,” says Peziol, noting previous research showing that throughout their lifetimes, devoted mountain lion mothers spend 82 percent of their time with their kittens. The young stay with their mothers until they’re about 18 months old for protection, food, and intensive mountain-lion-survival-skills training.
Time for Kittens
The research aimed to provide clear, non-judgmental, science-based guidance for members of the public to take action on what Elbroch refers to as “the emotional impulse to protect mountain lion kittens.” (See a den of kittens found near a highway.)
Panthera’s recommendation that wildlife managers protect kittens by delaying hunting season until December 1 would allow hunters to detect family groups in the field. Hunters could avoid accidentally hunting females with young, for instance by being able to identify kitten tracks in the snow.
“Almost all hunters want to preserve populations and avoid killing mothers with young kittens,” Elbroch says. “This is one step that would make a real difference for mountain lion families. We call it common sense conservation.”