The elk or wapiti (Cervus canadensis) are plentiful in Yellowstone. Only the males have antlers, which start growing in the spring and are shed each winter. The largest antlers may be 3-4 feet long and weigh 40 lbs. Antlers are made of bone which can grow at a rate of about an inch per day per day. While actively growing, the antlers are covered with and protected by a soft layer of highly vascularised skin known as velvet. The velvet is shed in the summer when the antlers have fully...
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The elk or wapiti (Cervus canadensis) are plentiful in Yellowstone. Only the males have antlers, which start growing in the spring and are shed each winter. The largest antlers may be 3-4 feet long and weigh 40 lbs. Antlers are made of bone which can grow at a rate of about an inch per day per day. While actively growing, the antlers are covered with and protected by a soft layer of highly vascularised skin known as velvet. The velvet is shed in the summer when the antlers have fully developed. Bull elk may have eight or more tines on each antler; however, the number of tines has little to do with the age or maturity of a particular animal. The formation and retention of antlers is testosterone-driven. After the breeding season in late fall, the level of pheromones released during estrus declines in the environment and the testosterone levels of males drop as a consequence. This drop in testosterone leads to the shedding of antlers, usually in the early winter.
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