The goa (Procapra picticaudata), also known as the Tibetan gazelle, is a species of antelope that inhabits the Tibetan Plateau.
Description
The goa is a relatively small antelope, with slender and graceful bodies. Both males and females stand tall at the shoulder, measure in head-body length and weigh . Males have long, tapering, ridged horns, reaching lengths of . The horns are positioned close together on the forehead, and rise more or less vertically until they suddenly diverge towards the tips. Females have no horns, and neither sex has distinct facial markings.
thumb|left|From The book of antelopes (1894).
The goa is grayish brown over most of its body, with its summer coat being noticeably greyer in colour than its winter one. It has a short, black-tipped tail in the center of its heart-shaped white rump patches. Its fur lacks an undercoat, consisting of long guard hairs only, and is notably thicker in winter. It appears to have excellent senses, including keen eyesight and hearing. and the snow leopard.
Reproduction
For much of the year, the sexes remain separate, with the females grazing in higher altitude terrain than the males. The females descend from their high pastures around September, prior to the mating season in December. During the rut, the males are largely solitary, scent marking their territories and sometimes butting or wrestling rival males with their horns.
Gestation lasts around six months, with the single young being born between July and August. The infants remain hidden with their mother for the first two weeks of life, before rejoining the herd. The age of sexual maturity in goas is unknown, but is probably around 18 months. Goas have lived for up to five years and seven months in captivity. The population in Ladakh, less than 100 individuals, continues to decline. Within Ladakh, its distribution was spread as far west as the Tsokar Basin in the beginning of the 20th century, but today is confined to the Hanle Valley and the neighbouring areas, such as Chumur. Presently gazelles are suffering not only from poor pasture conditions, but also from problems associated with small populations such as lack of genetic diversity in the population, which makes them less resistant to diseases.
Goa populations in both Ladakh and Tibet seem to be declining precipitously and are threatened with extinction, at least in some regions. A small population also exists in northern Sikkim, right at the border between India and Chinese-controlled territories, apparently moving back and forth between the countries.