Members of the deer family, or cervids, are famous for the antlers that are grown every year by the males (except for the caribou, or reindeer as they are known in Eurasia, where the females also grow antlers, albeit slightly smaller). Large antlers are the desire of sportsmen across the globe, and are the causal agent of that psychological disorder that afflicts North American hunters every fall known as “buck fever”. Horns are different from antlers, where horns are permanent structures, as seen on cattle or bison, and are covered with a keratinous layer, similar to hooves or fingernails. Antlers are re-grown every year, and are covered in a layer of thin skin packed with blood vessels called velvet. The velvet feeds the growth of the bony material underneath, and early spring is a good time to spot mule deer bucks and bull elk or moose as they begin the process of growing antlers.
This photo was just taken last week, and shows new antlers on a mule deer just as they are starting to grow. Injuries to the velvet at this point can affect the growth of the antlers, giving rise to non-typical racks, or a pair of antlers that are not symmetrical.
This photo is from last year, but shows the antler growth by mid-June, about a month later.
Finally, this photo shows the antlers by mid-July, with a lot more differentiation between tines. This is, for obvious reasons, also one of our favorite wildlife pictures on Blue Valley Ranch. (Photo credit: Josh Richert)
In late-summer, early-fall, the growing bone underneath the velvet begins to mineralize and harden. Essentially, the bone dies and the velvet falls off, revealing the mature antlers beneath, as you can see with these two bucks, photographed in mid-October. Once mature, the antlers are ready for battle as the bucks compete with each other for females during the rut, or breeding season. A few months later, they will fall off and the process will start all over again next year.