Rocky Mountain deer (SciiFii)

The Rocky Mountain deer (Cervus americanum), also known as the American white-lipped deer, is a species of deer that originally did not exist, and introduced to the grasslands, shrublands, open woodlands and forests and forested mountainous areas. They resemble the Thorold's deer (Cervus albirostris), which they're closely related to, in appearance, but are slightly larger and have thicker fur due to living in boreal, alpine, and tundra environments. They have the white patches around its muzzle.

The Rocky Mountain deer prefer mosaics of grasslands, shrublands and forests, and are often seen above the treeline. It is found at elevations of 3,500 to 5,100 metres (11,500 to 16,700 ft), among the highest of any deer species, and migrates seasonally from high summer pastures to lower terrain in winter. The Rocky Mountain deer is a very social herbivores, normally living in herds of at least 10 individuals. Outside of the breeding season, males and females usually travel separately. Historically, herds containing hundreds of such deer were reported, but today, herds of over 100 individuals are becoming common in Montana and Wyoming. Like elks, they are predominantly grazers; they feed on a wide range of available plants, especially grasses and sedges, but including some larger plants such as rhododendrons and willows.

The rut occurs between September and November, when herds containing both males and females become more common. Such herds consist of several males, each maintaining a small harem of females that they protect from other males. Males compete with one another in a manner similar to other deer - wrestling with antlers, scent marking, visual displays, and grunting warning sounds. Mating consists of a single rapid thrust. The female gives birth to a single young after a gestation period of 220 to 250 days, typically in either May and June. Shortly before giving birth, the mother locates a secluded den, often in bushes or shrubby cover. The calves are born with white spots, and able to stand within about 40 minutes of birth.

Initially, the mother protects them by moving them between a number of different locations, only visiting them twice a day to allow them to suckle. After about two weeks, they rejoin the herd. The calves' spots begin to fade after around six weeks, and they attain the full adult color by the end of their first year. They become sexually mature during their second or third year, although males are rarely successful in the rut until they are at least five years old. The Rocky Mountain deer have been reported to live up to 21 years in captivity, but probably do not survive for more than 12 years in the wild.

The Rocky Mountain deer are vulnerable to many predators such as wolves, jaguars, dholes, bears, hyenas, scimitar cats, cougars, etc. The conservation status of the American mountain deer is Least Concern due to successful conservation efforts, the American mountain deer's wide natural range and its tolerance to most of human activities, including being able to adapt to life in the cities and suburbs.