White-tailed Deer and Protein Needs

Many hunters, land managers, and biologists believe that a 16% protein food source is needed for bucks to achieve maximum antler growth and does to achieve maximum fawn production. And this is true, but it’s not. Protein levels are of most importance during specific times of the year.

For antler growth, that period is from late winter through the end of the antler-growing period. For fawn production, the period when protein levels are most critical to does is during fetal development and lactation. And in general, protein levels are highest in native forage during spring and fall and are lowest during summer and winter. This makes sense.

But what about when protein becomes limited, such as during the summer and winter? Deer can compensate for this seasonal availability of protein through protein recycling, but this means proteins will be used for critical functions first. It’s not a coincidence that antler growth and fetal fawn development coincide with the seasonally high level of proteins during the spring.

Although deer can survive a dry spring, bucks will produce antlers that are smaller than their potential and does may abort fawns prior to birth or abandon them shortly thereafter. High protein levels are not critical for deer survival, but “excess” protein can definitely increase antler size, as well as fawning rates in most cases. However, I’ve seen properties that feed free-choice protein year-round fall victim to low fawn recruitment.

Why? Because deer will eat from a feeder, but they still pick up environmental cues that tell them how they should act. If habitat is in poor condition from too many deer or drought conditions, deer pick up on environment — and that dictates their behavior.

If you are interested in supplementing white-tailed deer, remember that winter and summer are the criticial times with regards to protein availability, but providing additional protein during the spring and fall will enhance the body conditions of deer on your property and put them in better shape for those tough periods.