Ecology of the Andean Bear

Most people do not know that the elusive Andean Bear, known for the white or brown marking around the eyes, lives in the Ecuadorian Andes. It the only species of South American bear, found in a narrow strip running from western Venezuela through the Andes in Columbia, Ecuador, Peru, and Bolivia, and ending in Northern Argentina. Their distribution is predominantly restricted by geographical boundaries like high mountains or deserts (for example: the Atacamas desert accounts for the complete lack of bear populations in Chile). It is an "endangered" species in Ecuador, mostly due to habitat fragmentation caused by livestock farming and logging. Farmers often shoot these bears because they eat corn (this is illegal).

The Andean Bear is not the enormous hibernating bear of the northern hemisphere. It is comparatively thin, with a shorter nose, similar to that of a dog. This bear has a long, thick black coat, except around the muzzle, which is tawny or brown, often with white marks around the eyes (from which it gets its common name, the Spectacled Bear) that may extend to the throat.

Males are much larger than females, with males often growing to a size of 2.2 metres from head to toe. The largest male Andean bear ever recorded measured an incredible height of 2.4 metres. Males may weigh up to 200 kg. Females are much smaller, rarely exceeding heights of 1.6 metres from head to toe. Maximum ages are 35 to 40 years. However, this is an age only ever reached in captivity. It is believed bears in the wild rarely live longer than 20 years due to the stresses of life in the wild and sporadic food availability.

Andean Bears are agile climbers, not only of trees but also of rock walls. They are also very good swimmers. The principal sense of the bears is olfaction (smell), and their vision and hearing senses are inferior. Andean Bears are very timid. There has never been a report of a wild Andean Bear attacking a person. If they see you they will turn around and run or climb the nearest tree.

Andean bears have a varied diet. Like all ursids they have a sweet tooth, and are predominantly vegetarian, although are generalistic opportunistic feeders. In the forest they eat palmitos (hearts of palm), the soft insides of suro (Chusquea spp) (a kind of bamboo), the soft bases of huaycundos (Bromeliaceae), and various types of fruits. In the paramo, they eat the soft bases of Puyas (Puya sp) and a berry-like fruit called mortiño (Vaccinium sp). With forests increasingly being cultivated and replaced by cornfields, bears have developed the taste for sweet corn. Although this is not a natural food source, in the corn season a bears diet consists of a large proportion of corn.

As with all animals, a source of protein is necessary for tissue growth. They dig holes in the earth in search for beetles and insects as a source of protein, and occasionally feed on small mammals. In very rare cases, in some parts of Ecuador, there have been incidents of bears attacking livestock. The reason for this is believed to be a lack of food in the forest forcing bears to search for food elsewhere. Once a bear has eaten meat, they often get a taste for it and return to hunt again. As bears aren’t natural born killers like felines, they don’t go for the jugular for a quick kill and easy meal. The bears actually tend to jump on the cows back and take chunks out of the tender shoulder region whilst the cow is still alive. If the cow survives this attack, then they will certainly be killed by the bears immense force shattering the animals skeleton as is dragged back to the cover of the forest.

Newborn cubs measure about 18 cm and they weigh from 300 to 500 g. They open their eyes around 42 days of age, and within three months of birth are able to follow their mother. In times of danger, or if they tire, they can ride on her back. Mature males occasionally accompany the family group, but this is unusual. It is not known exactly how long cubs stay with the mother in the wild, but we estimate this period to be around 14 months, having seen the same female with the same cubs after a 13-month period.