Elk

The elk is a large animal of the ungulate order Artiodactyla, possessing an even number of toes on each foot, similar to those of camels, goats and cattle. It is a ruminant species, with a four-chambered stomach, and feeds on grasses, plants, leaves and bark. During the summer, elk eat almost constantly, consuming between 4 and 7 kilograms (8.8 and 15.4 lb) of vegetation daily. In North America, males are called bulls, and females are called cows. In Asia, stagand hind, respectively, are sometimes used instead. Elk are more than twice as heavy as mule deer and have a more reddish hue to their hair coloring, as well as large, buff-colored rump patches and smaller tails. Moose are larger and darker than elk; bulls have distinctively different antlers. Elk gather in herds, while moose are solitary. Elk cows average 225 to 241 kg (496 to 531 lb), stand 1.3 m (4.3 ft) at the shoulder, and are 2.1 m (6.9 ft) from nose to tail. Bulls are some 40% larger than cows at maturity, weighing an average of 320 to 331 kg (705 to 730 lb), standing 1.5 m (4.9 ft) at the shoulder and averaging 2.45 m (8.0 ft) in length. The largest of the subspecies is the Roosevelt elk (C. c. roosevelti), found west of the Cascade Range in the U.S. states of California, Oregon and Washington, and in the Canadian province of British Columbia. Roosevelt elk have been reintroduced into Alaska, where the largest males are estimated to weigh up to 600 kg (1,300 lb).[25] More typically, male Roosevelt elk weigh around 300 to 544 kg (661 to 1,199 lb), while females weigh 260 to 285 kg (573 to 628 lb). The smallest-bodied subspecies is the tule elk (C. c. nannodes), which weighs from 170 to 250 kg (370 to 550 lb) in both sexes. Only the males have antlers, which start growing in the spring and are shed each winter. The largest antlers may be 1.2 metres (3.9 ft) long and weigh 18 kilograms (40 lb). Antlers are made of bone which can grow at a rate of 2.5 centimetres (0.98 in) 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 Siberian and North American elk carry the largest antlers while the Altai wapiti have the smallest. The formation and retention of antlers is testosterone-driven.[29]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. During the fall, elk grow a thicker coat of hair, which helps to insulate them during the winter. Males, females and calves of Siberian and North American elk all grow thin neck manes; female and young Manchurian and Alaskan wapitis do not. By early summer, the heavy winter coat has been shed, and elk are known to rub against trees and other objects to help remove hair from their bodies. All elk have small and clearly defined rump patches with short tails. They have different coloration based on the seasons and types of habitats, with gray or lighter coloration prevalent in the winter and a more reddish, darker coat in the summer. Subspecies living in arid climates tend to have lighter colored coats than do those living in forests. Most have lighter yellow-brown to orange-brown coats in contrast to dark brown hair on the head, neck, and legs during the summer. Forest-adapted Manchurian and Alaskan wapitis have darker reddish-brown coats with less contrast between the body coat and the rest of the body during the summer months. Calves are born spotted, as is common with many deer species, and they lose their spots by the end of summer. Adult Manchurian wapiti may retain a few orange spots on the back of their summer coats until they are older. This characteristic has also been observed in the forest-adapted European red deer.