It was May 1, 2014, and we had spent a frustrating five hours climbing mountains, crossing rivers, and straddling log jams in pursuit of F51’s orphaned cougar kittens. We never glimpsed them, but their movements clearly relayed that they were alive and mobile.
It had been 31 days since their mother had died, during which the U.S. Forest Service winter closures for elk had restricted us from trying to see them to assess their health. We had so many questions—how were they surviving? Were they injured? As of May 1, the orphaned sisters were eight months old.
F51, an adult female mountain lion tracked by Panthera’s Teton Cougar Project, was killed by an adult male cougar in a chance encounter at the edge of her home range (See: “Intraspecific Killing Among Cougars.”) and at that time, we were quick to assume her kittens were doomed. Who’d have faulted our pessimism? Not other biologists, certainly, as the numbers are stacked against cougar kittens orphaned in the wild.
In a 10-year New Mexico study, 10 of 10 kittens five months old or younger died when orphaned, whereas an eight- and ten-month old survived (Logan and Sweanor in 2001). In a Utah study of 11 orphaned kittens, five died between the ages of 4-6 months, a nine-month old was killed on a depredation permit after being independent for six weeks, and five others disappeared without researchers determining their fate (Stoner et al. 2006). In more recent research in the northern Yellowstone Ecosystem and the Garnet Mountains of Montana, only 13 of 22 kittens that became independent (either orphaned or dispersed) between 7-12 months survived (Newby et al., unpublished data).
But perhaps these numbers obscure the truth: Orphaned or dispersing kittens are rarely monitored intensively enough to determine their fate. Thus, perhaps it’s more accurate to say that we’re still deciphering what factors influence orphaned kitten survival, as well as what percentage of orphaned kittens actually survive. This is especially important in areas where cougar hunting is legal, and the question as to what happens to kittens orphaned when their mothers are killed has yet to be answered. Orphaned kittens in research projects across the U.S. typically just disappear, and researchers are taught to assume the worst.
We had much better luck on May 2, when we were at it again. We found them approximately half a mile south of their mother’s usual range, and eight miles from the place where F51 had been killed. Together with Jeff Hogan, professional cameraman and owner of Hogan Films, and his assistant, Neal Wight, I witnessed something amazing, even miraculous. We had quietly perched ourselves atop a cliff face immediately above the kittens, as the afternoon sun descended at our backs. We discovered F99 and F75, orphaned sisters, lying peacefully in the sagebrush.
F75 was quick to rise. She stood, pausing to look in the direction of F99. She stretched and yawned, typically cat-style, and then began to saunter in the direction of her sister. F75 brushed F99 lightly as she meandered through the sagebrush, and then she dropped into a dry watercourse. She followed it perhaps 20 yards to the north to an old cow elk carcass I hadn’t taken in until that point. The carcass appeared bare, just skin surrounding a gaping hole where the rib cage and other bones jutted skyward. We couldn’t imagine there would be much sustenance left on the carcass, but she began to feed. She attacked that old bag of bones with an enthusiasm that betrayed her will to live. We paused to look at each other, and whispered in unison, “She’s going to make it!”
Aggressively, she ripped at the dried shell of skin that protected something I only hoped was more palatable beneath. She tore out great tufts of fur and wrestled to move the massive carcass that dwarfed her. She fed for maybe 20 minutes before returning to her sister. They nuzzled, and F75 plopped down, intimately draping a leg across her sister.
The question of how were they surviving was answered. In some ways, spring was actually a perfect time to be orphaned. Abundant ungulate carcasses were being revealed on the landscape as snows receded; some killed by predators, others by winter, disease, or just old age.
But regardless of the why, their bodies were welcome sustenance for emerging bears, numerous other scavengers, and it seems, orphaned cougar kittens as well. Clearly, ungulate carcasses that accumulated in winter were a real boon for F75 and F99, but I worried that they wouldn’t last. Scavengers would be competing to clean them as quickly as possible, and invertebrates were beginning to appear. Maggots and beetles can strip carcasses in short order.
We sat in continued silence, each of us completely amazed and engaged by the scene below us. F75 moved away from her sister to lie on her own. She chirped a few times—perhaps still looking for their mother? The pair had grown substantially since I’d last seen them, though they were both small and bore the characteristic fluffy fur that marked them as kittens. Their ears were both cropped short, evidence of frostbite suffered the previous December when the Jackson area experienced especially bitter temperatures for several weeks. But the kittens appeared stocky and to have food in their bellies.
We watched the pair for well over an hour, until darkness had nearly settled in. We snuck back up the slope and away to the north so as not to disturb them. It was like a Disney movie come true—two orphaned kittens had survived, against all expectation, and were making their way in the world. The challenges ahead were very real, in the form of wolves, grizzly and black bears, coyotes, other mountain lions, learning to hunt, establishing a range, and surviving another winter yet to come. But perhaps their chances were much better together than if each of them were on their own.
Within a week of watching F75 and F99 below the cliff, the horrible happened—they separated. We’re not sure why, perhaps they were chased by a predator, perhaps for some other reason, but the fact was that one morning we discovered the two sisters in separate locations out in the flat country of Grand Teton National Park.
They were as vulnerable as they could be, lacking many trees to climb should large predators appear. F99 may have realized the risks and quickly looped back to where we’d found them in nearby mountains in early May. F75 however, wandered further and further afield, traveling approximately 10 miles, through sage flats, over Blacktail Butte and further north past the famous historic barns on Mormon Row. We discovered her feeding on another old decaying elk carcass tucked in between waist-high sagebrush.
F99 in the meantime moved further east, the gap between them increasingly expanding. We documented each kitten feeding on different old carcasses they’d found. F75, especially, seemed to be seeking her sister (or perhaps her mother)—we often watched her from afar calling (chirping) for long periods. It was a nerve wracking 10 days for us. Was their separation foreshadowing tougher times for the both of them?
No, it seems. F75, eventually looped back south and then east, following the path of her sister. F99, also looped back west and the two were reunited near the area where we first glimpsed them in the beginning of May. How we wished we’d seen those initial moments of reunion! But alas, none of us were present. Instead, we were lucky enough to watch them the next day.
F75 and F99’s story continues to surprise and inspire us. Their next big challenge is learning to hunt. Summer ground squirrels and grouse provide F75 and F99 opportunities to practice stalking and killing, and new deer fawns and elk calves that are being born as I write this might provide larger targets as they master new skills.
But for now, our update is this: Against incredible odds, orphaned cougar kittens F75 and F99 persevere. Please join us and follow F75 and F99, as well as other cougars, on the Teton Cougar Project Facebook page.