Wildlife Filmmaker Forgot Cameras Inside Grizzly Dens — 10 Years Later, Stunning Footage Emerged
When Casey Anderson, a wildlife filmmaker, forgot his cameras inside two grizzly bear dens north of Yellowstone, he certainly didn't expect what happened next. The cameras remained in place for a decade, from 2015 to 2025, silently capturing the movements of cave visitors. Despite being grizzly dens, many other animals also ventured into them, unknowingly getting captured by the cameras. From a mountain lion to a coyote and, of course, the grizzlies, the cameras somehow captured them all. Speaking to Cowboy State Daily, Anderson admitted that the incident was entirely a happy accident. “I wish I’d done it on purpose,” he told the outlet.
The filmmaker revealed that he had placed "camera traps" in the dens in 2015 and later got busy with other projects, completely forgetting about his earlier experiment. The thought of checking back the cameras never entered his mind until recently. In the summer last year, he and some of his friends finally decided to hike to the remote and high-altitude location to check on the camera traps. They were amazed to see one of the cameras fully intact after all those years. Though the other one was scratched out, possibly by a bear, its SD card was unharmed and packed with recorded footage. According to the outlet, the cameras had recorded about 300 clips of the wild animals venturing through the dens.
It's a great feat not just because the cameras captured incredible footage of the wildlife, but also because the grizzly dens were a rare find. Anderson revealed that the dens are located in a remote area as bears seek isolation for sleeping. The extremely remote and unpleasant places are ideal for the creatures to sleep undisturbed, especially during winter hibernation. Contrary to popular belief, they seldom use the "bear caves" to hibernate and instead dig their own dens in the sides of steep alpine slopes. The cozy and compact pocket retains heat in the winter, allowing them peaceful hibernation. “There are plenty of little caves up there (in the mountains), but the bears don’t use most of them,” Anderson said.
Considering how rare it is to spot a grizzly den, Anderson was surprised when he found not one but two of them during his 2015 trek. He couldn't miss the opportunity of adding a camera trap in hopes of getting interesting footage for his Endless Venture YouTube channel. While the bears occupy their dens through the winter, they don't hang out there after waking up in the spring. They spend the rest of the seasons wandering about, searching for food and seeking refuge in open resting places and the shadow of trees. “The kind of Disney storybook ‘bear cave thing,’ that doesn’t really happen,” the wildlife filmmaker added. In these seasons when the grizzly bear dens are vacant, it is visited by other wild creatures, and some of them have been captured on tape, thanks to Anderson's experiment.
“All these animals, they go to check in to see, ‘Who’s in this territory?’” he said. “You’ll see where them mark on top of each other’s marks," he added. Among the 300 clips, Anderson was most captivated by the footage of a mountain lion’s daytime venture. “You first see this shadow, then this big cat comes in, and it’s a beautiful mountain lion,” he recalled.
You can watch the video here.
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