There is an abundance of wildlife in Colorado that you don't see in cities- or even suburbs, across most of the country. Most of it is large. Most of it is shy of humans. And most, if not all, will not hesitate to absolutely f*ck you up if you get near it. Everyone loves to make fun of the tourists in Yellowstone who get out of their cars and walk up to the bison, then turn around and act surprised when the elk in Estes Park get aggressive.
No matter how friend-shaped the animal is, it is not your friend and it will not hesitate to remind you- no matter how in-tune with nature you think you are.
bears
I'm going to start this page off with bears. I count black bears in the same family as raccoons. They're a little bigger, but just as craft and they love getting in the trash.
Black bears are the only bears left in Colorado. Grizzlies were hunted out completely in the 1950's, and while some black bears can be brown or cinnamon colored, I promise you they're still black bears. Black bears tend to be much more wary of humans and will usually keep their distance. This does not mean they're safe to approach, especially if they have cubs. Walking up to a momma bear and her babies is a surefire way to check 'mauled by a bear' off your bucket list. If it makes you feel safer, you can carry bear spray but the sound of your voice should be enough to scare it off. If you're going to carry bear spray, for god's sake, know how to use it. DON'T fire it into the wind.
In all my years visiting and living in Colorado, I have seen a grand total of five bears. That's right, five. Of those five, two were in dumpsters and three were on the main streets of ski towns. I have seen exactly zero bears on the trail. Not to say they aren't there, but you shouldn't let your fear of bears deter you from hiking.
If you do happen to come across a bear on the trail- and I mean these seriously- Don't panic. Don't run. Clap your hands, yell (and I mean YELL), and make yourself look big as you slowly back away. That should be enough to scare it off. If it's not, you'd better be ready with the bear spray.
wolves & kitty cats
Wolves were recently reintroduced to Colorado. Since then, there have only been a handful of sightings. I would apply the same rules to them as I would to bears. Do not approach. Do not pet. I don't care how much it looks like a big puppy. Make yourself known and slowly back away.
Colorado has a few different species of big cats- bobcats, lynx, and mountain lions. They are the most elusive of the state's big game and are rarely seen. Bobcats are the smallest, with speckled tan fur and foot-long tails. Lynx are bigger, about the size of a golden retriever. They have gray fur, stubby tails, and big tufts of fur on top of their ears. Mountain lions are the biggest, also known as pumas or cougars. They're close in size to a Mastiff or Great Dane, with tan fur and long tails.
I've never seen any of these myself. I know one person who's seen a lynx, and I've seen mountain lion pawprints. But you know what they say, if there's a big can around, you won't see it. It'll see you.
elk
Elk are to Estes Park what bison are to Yellowstone- idiot magnets. Every year there's at least a few morons who think they can walk up to an elk and take a picture because it's just a big, dumb animal. And every year, I get to watch them prove Darwin was right. Because they are big dumb animals- that either happen to be in rut season or calving season during Colorado tourist season- and that is not a good mix.
The thing people can't seem to grasp is that elk and deer are not the same. Elk are twice the size of a white tailed deer, and unlike those deer, elk won't run if you step on a leaf wrong. They'll see you as a threat to their mate or their young and treat you as such. They are not something you want to face in a headbutt contest, so stay in your car. If you see them on the trail, give them plenty of space. Don't be that idiot.
bighorn sheep & mountain goats
I see these two get confused more often that elk and deer. Which is weird, because they look nothing alike. Bighorn sheep have short gray coats and large, rounded horns. Like the Colorado State University mascot, or those two idiots from Brother Bear. (No, you shut up!!) Mountain goats are bigger, with long, shaggy white fur and small black horns. I wouldn't be at all surprised if they were responsible for some of that Yeti folklore that's out there.
Both bighorn sheep and mountain goats can be found in the mountains. I've seen bighorn sheep all along i70 west of Idaho Springs. There's even a lookout point right near Georgetown where you can often see them on the hillside, and they have a radio station dedicated to tracking those herds. Mountain goats, however, are a lot less common. I've only seen them around high-alpine lakes and on the sides of Fourteeners. Both are wary of humans but again, will not hesitate to headbutt you to protect themselves.
moose
Moose are the most dangerous of Colorado's big game by a long shot. They're huge- no, whatever you're picturing, they're bigger. They're also nearsighted and aggressive, which is not a good combination in any species.
If you see a moose, stay away from it. They will charge you if they feel even the least bit threatened, and even if the antlers miss you it'll still be like getting hit by a Ford F-150. And no, I'm not exaggerating. If you see one coming down the trail toward you, treat it like the T-Rex in Jurassic Park. Get behind something solid, stay quiet, and wait for it to pass.
I know this sounds a bit ridiculous, but I'm dead serious. They will actually try to kill you if they think you're a threat. Stay away, only take photos if it's through a telephoto lens, and don't be like those morons at Yellowstone.
