In all likelihood, this is the work of man. Conventional wisdom tells us that deer can not put on clothing, no matter how simple the design. And yet, let me tell you about deer.
Not long ago I moved to a small town nestled in lake country. My first week here I ran into a bear as one might run into a neighbour in line at the grocery store, both of us picking up some berries from nature's free shop. Foxes, wolves and otters are common sightings, too, but none of them so bold as the deer.
A deer can jump a six foot fence like a tissue floating on wind, so when I decided to garden, I caged the whole thing up. I look left and I look right, and then I open the wood and wire door to check on my pumpkins to an audible snort, deer just behind me, waiting to get at my peas.
A deer figured out the gate to the deck and ate all my tomatoes. I chased after one, trying to help, because it got the whole tomato cage stuck on it's head like an avant-garde muzzle, it wore it for a week. A deer begged my friend for her wendy's fries and ate them from her hand, we posted a picture and three people said "Oh yeah, that's Bernie." A deer broke my plastic garden chair by trying to sleep in it. Just today, I was scattering salt and sand over the walkway when a deer pranced over and stuck it's whole head in the scoop/shaker thing while I still held it.
I don't encourage the deer, I don't feed them or start conversations, but to them we're all one weird tribe. They bring their kids to the yard in the morning to hang out, sometimes waiting by the door for me to come outside with my coffee. Sometimes they have neon flagging tape or chicken wire stuck in their antlers, and they won't let me take it out. Sometimes they have orphaned mits in their mouths, I don't know where from, and they throw them at each other in a game I don't understand.
I'm not saying a deer could put on a vest, no, but it was probably their idea.
I’d bet this is someone’s “pet” deer that they don’t want shot and are trying to signal that. I’ve heard of people putting reflective collars and things like that on deer that they’ve kept as pets, to try to deter hunters from shooting them.
If that’s what it is then I totally get the impulse to help a wild animal yourself, but the average person VASTLY overestimates their knowledge of what wildlife needs to be healthy. Always contact a wildlife rehabber if you find wildlife in distress!
And then there's the dude I ran into at a bonfire a couple months ago talking about how he got a deer to trust him enough to come on his property and let him hand feed it and the instant deer season starts he was going to shoot it.
According to the article nobody in McBride can figure out how this happened.... Yeah McBride is like that... However a glance at the photo suggests that alcohol was involved.. I am pretty sure that the deer did not get its front legs into the sleeves by itself and I suspect it also had some help with the zipper....