I'd have my back against something other than a sapling pine.

I heard that sound coming out of the canyon below my camp once. I almost packed up and moved.

That is a game call. They are trying to call a lion. "We'll see if this works." About 12 seconds in.

I experienced this exact same thing near Kremling Co one cold brisk morning while muzzle loader elk hunting. About 3 in of fresh snow on the ground at day break while standing on the side of a small meadow when that exact same sound came out of the dark timber in front of me. It was surreal as it continued for about 5 minutes coming closer and closer. Finally in front of me was a large adult and 2 small lions who upon seeing my tracks in the snow made a beeline in the opposite direction. Having a single shot rifle at the time made the experience even more exciting. This was truly a memory anchored in my memory forever!!!!!!!!!

Would love to hear it for myself.
It’s all in the mind though. If you hunt out west, you have been in proximity of apex predators at times - whether you hear them or not.

Is a black bear a apex predator?

Yeah, but they’re almost never dangerous to hunters. Same with mountain lions. Grizzlies can be (especially in certain areas), but anywhere you go the odds of being attacked by an unmolested apex predator are infinitesimal. It happens sometimes. Falls happen sometimes. Lightning strikes happen sometimes. Chit happens sometimes.
Heck, tree-huggers hike and bike all over the west - doesn’t stop them.
I carry bear spray when trout fishing in grizzly country, but if I leave it at the cabin I don’t go back for it.

as pappy once said: " nothen more dangerous than an aprex preditor with a rifle in hand thats scared of hogs. tis the reason i hunted at night with flashlight off & pistal on hip, i'm scared of me own shadow. " i got cheap posts.