I can say some things effect why deer shed early, but not as sure why late. Early is easy, its almost always stress related, either fatigue, injuriy or even sudden poor feed. It drops the testosterone production, and off go the antlers. On the other side, keeping them so long, Im not so sure, but I have a hunch. Last two years my bucks were carrying their antlers into March and even April. No big deal, as they started new growth right away. But, I always liken antler growth to a barometer of the animals health or condition. So, I figured maybe the high energy/protein feed might be the culprit. That is, not having a stress "trigger" for the shedding to occur at the same time as the wild deer. So I pulled the grain and left just hay for a week. Hay is great for them, but the change seemed to do it. They all seemed get "synchronized" and shed. This year all went very well, the regular shed dates were matched, and the late shedders shed on time with the rest of them.

So, maybe the high octane food plots out there are keeping the deer healthier and the deer arent being stressed as much. I dont really know, but as long as the antlers are big Im happy.