Andean Deer, Taruga

Description

The taruca is a medium-sized deer with a heavy body. It measures 128 to 146 cm (50 to 57 in) from head to rump, with a 11 to 13 cm (4.3 to 5.1 in) tail, and stands 69 to 80 cm (27 to 31 in) tall at the shoulder. Adults weigh between 69 and 80 kg (152 and 176 lb). As with most deer, males are significantly larger than females.

It has sandy brown hair over most of its body, with white patches on the underside of its head, neck, tail, and genital region, and on the inner surface of its fore-legs. While females often have a dark brown area on the forehead, facial markings are much clearer in the males. The exact patterns vary between different males, but in general there is a black behind the nose, and a black Y or V pattern over the forehead and snout.

Male tarucas have antlers, typically measuring 27 cm (11 in) in length once fully grown. Unlike all other South American deer, except for the closely related huemul, the antlers consist of just two tines, branching close to the base, and with the posterior tine being the larger. Males also possess canine teeth in their upper jaw, which females usually, but not always, lack.

Distribution and habitat

Tarucas are found only in the Andes mountains, from central Peru, through Bolivia and extreme north-eastern Chile, and into northern Argentina. In Argentina, they are found between 2,000 and 3,000 m (6,600 and 9,800 ft), but the elevation of their preferred habitat gradually rises as they approach the equator, until it reaches 3,500 to 5,000 m (11,500 to 16,400 ft) in Peru. Within this region, they are found in grasslands marked by occasional shrubs and rocky outcrops, typically close to water. There are no recognised subspecies.

Diet and behaviour

Despite living in grasslands, the taruca feeds mainly on the local bushes, shrubs, and herbs for much of the year, but supplements this diet with grasses during the rainy season. Plants commonly eaten include dwarf gentian, ragworts, lupins, senna, valerian, and clubmosses. Tarucas may also feed on agricultural crops, such as alfalfa, barley, and potato plants.

Tarucas are gregarious, but do not live in stable herds, with individuals moving between groups of up to thirty members each over the course of a few days. Their populations are scattered, due to their need for relatively specialised habitats, with population densities as low as 0.15/km² (0.39/sq mi), even away from human habitation. Individual groups are typically led by the females. During the breeding season, males may compete with one another, displaying threatening behaviour by raising their forelegs one at a time and pointing their antlers towards one another.

Reproduction

The rut lasts from May to July, during which time the deer segregate into smaller groups with a single adult male. Males drop their antlers immediately after the breeding season finishes, in September, with the new pair beginning to grow in December, and losing the velvet by February. Pregnancy lasts for 240 days, so that the single fawn is born between January and March, coinciding with the rainy season. Twins have been observed in captivity, but are rare. The mother leaves the group in order to give birth, and keeps the fawn hidden behind rocky outcrops for the first month of life.