The Quality Deer Management Association (QDMA) reports that they've been seeing these "bullwinkle deer" since the mid-2000s, and blame this phenomenon on a bacterial infection. Exactly what bacteria are responsible, or how the deer are contracting the infection, is still unknown. Have you ever seen anything like this?
First it was chronic wasting disease showing up in deer herds, prompting hunters to wonder if this "mad cow disease" could be stopped. Then it was EHD and blue tongue disease, viral diseases that seem to pop up in a different location every year and put a dent in a local deer population. Now, a new infection is starting to crop up all over the whitetail's range — it doesn't even have a name, but the animals infected with this bacteria are called "Bullwinkle deer," and it's not hard to see why.
The Southeastern Cooperative Wildlife Disease Study unit has been keeping tabs on this still-rare bacterial infection since the early 2000s, having received less than a dozen samples since 2005. Deer infected with this bacterial wind up with swollen muzzles due to inflammation, giving them a strange moose-like appearance.
The Quality Deer Management Association references SCWDS findings on the infection:
"While the Bullwinkle infection is no doubt uncomfortable for the victim, it doesn't appear to be lethal. All of the samples have been submitted from deer killed by hunters. QDMA has also received trail-camera photos of Bullwinkle deer that appeared otherwise healthy and that were photographed on multiple occasions over time. SCWDS said one person saw the same Bullwinkle deer several times over a period of two years."