Mountain lions are stealthy predators, and exceptionally well camouflaged in dry, grassy environments. Some prey animals have no idea they're being stalked until it's too late, and this photo shared by the US Fish and Wildlife Service shows why.
The picture, captured by a trail camera at Rio Mora National Wildlife Refuge, shows a seemingly peaceful scene with an elk grazing in the foreground, but look closely enough and you might be able to spot a mountain lion hiding in the background.
"The outcome of what happened between the elk and the lion remains a mystery," said the FWS in a Facebook post, "but it's a good reminder that nature is amazing and sometimes a little sneaky."
Can't see it? Check the comments on the post, where several keen-eyed posters have shared its location.
You might never have spotted a mountain lion in real life, but if you've been hiking or trail running in the American West, there's a reasonable chance that one has watched you. Attacks on people are very rare, but there are still some precautions you can take to keep yourself safe.
First of all, be mindful of your environment. You might not be able to see mountain lions, but you may be able to hear them if you leave your running headphones at home and stay alert. Be particularly careful in the early morning or late evening, when the big cats are most likely to be out hunting.
If you do find yourself in close quarters with a mountain lion, backing away slowly is much wiser than running, which can trigger the animal's chase response. Raise your arms and make yourself look as big as possible so the mountain lion recognizes that you're not a prey animal.
For more advice, see our guide what to do if you meet a mountain lion on the trail. In an absolutely desperate situation, bear spray also works on mountain lions, but you'll have to be prepared to make an extremely hasty retreat.
- Best binoculars and monoculars: enjoy wildlife watching from a safe distance
