The Story
A mountain lion stands in the palm litter in Tucson, lifts its chin, and peels its lips back off an open mouth, eyes squeezed nearly shut. It looks mid-yowl. It is doing something quieter than that.
This is the flehmen response, caught on a trail camera in May 2026. The filmer explains it plainly: cats and some other mammals carry an olfactory organ in the mouth, the kind snakes are known for, and they use it to read hormones. The grimace is the cat sampling the ground, not threatening anything.
The spot is the story. By the filmer's account, another mountain lion had urinated right here, and this one now has to cover the other lion's smell with its own. The filmer allows that the javelinas living on this ground could be part of the scent too. Either way, the cat is reading a message before answering it.
Scent and claw marks are how cougars claim ground. They mark territory with urine-scented mounds, and with claw marks on trees, stumps and occasionally fence posts, 4 to 8 feet up for an adult. Males defend territories from other males; a male's territory can reach 500 square miles. Cougars are solitary and elusive, and this one stands alone in the frame with whatever the last lion left.
The frame itself is daylight, with dry leaves underfoot and palm fronds and bare stems crowding in behind. The coat is plain tan, unspotted, with a whitish throat and chest. That uniform coat settles the usual trail camera question at once: bobcats are much smaller, with short bobbed tails and spotted, streaked coats.
Daylight is not the usual hour. Cougars are most active from dusk to dawn but may hunt at any time of day, and they rely on dense brush, steep canyons and boulders to stay hidden while they do. This thicket offers exactly that kind of cover, and the same stretch of country also holds a lion filmed stalking, probably after a javelina.
