Bear Species
Andean Bear
( Tremarctos ornatus )

Andean bear (Tremarctos ornatus) (cc) Stefan Willoughby
(cc) Stefan Willoughby

Physical description and lifespan

The Andean bear, also known as the spectacled bear, is medium sized, averaging 1.5–2.0 m in length. When adult, males are approximately one third larger than females, weighing 140­­­–175 kg. Andean bears have the shortest muzzle length (relative to head size) of all eight bear species.

The fur of the Andean bear is typically black, although in rare cases can be dark reddish brown. Most have cream-colored markings on the face, frequently encircling one or both eyes and extending down the chin to the chest. However, these cream-colored facial markings vary considerably and may be absent in some bears found in Bolivia.

No long-term field data are available on the wild lifespan of the Andean bear, but they are known to live 35–40 years in captivity.

Distribution

Andean bears are the only bear species found in South America, occurring in all three ranges of the Andes Mountains – from Venezuela south to the border between Bolivia and Argentina. They are very adaptable and inhabit dry thorn forests, rain forests, steppe lands and the paramo/puna grasslands between 250–4,750 masl.

An estimated 85 per cent of Andean bears live on the east slopes of the Andes between 1,000–2,500 masl, in the most productive cloud forest habitats.

Behaviour

Andean bears are generally solitary with the exception of family groups, but will feed in groups on Opuntia cactus and in maize fields. They can be active at night or during the day and do not hibernate. One of the more arboreal bear species, Andean bears spend considerable time feeding and resting in trees.

Reproduction

Andean bears, presumed to be consort pairs for the season, have been observed in the wild together between March and October. Although very little is known about the breeding ecology of Andean bears, it is believed that the gestation period ranges from as short as 160 days to as long as 255 days. As with the black bear, there is probably a period of delayed implantation.

It appears that most births occur between December and February, during the rainy season, although zoos in the southern hemisphere have reported a widely varying birthing dates. Andean bears usually produce one or two cubs, although litters of three to four have been recorded in the wild. Cubs are thought to remain with their mothers for approximately 18 months.

Diet

The Andean bear’s diet is generally herbivorous, although they are known to kill and scavenge domestic livestock, primarily cattle in the paramo (high elevation grasslands).

Conflict with humans

The greatest human densities in Andes Mountains are found at the low to mid-elevation range preferred by bears. Although Andean bears are culturally important for many indigenous groups in South America, attacks on livestock and cornfield raiding by bears and has brought them into conflict with humans across much of their range.

Cornfields located near the edge of forests are most vulnerable to raiding by bears because they are not always tended on a daily basis and frequently located away from human dwellings and protection. Bear attacks on livestock, primarily cattle, is considered a localised but important problem in many areas inhabited by Andean bears.

Although they may be significant predators of livestock, very little hard data exists regarding whether Andean bears are attacking livestock or are carrying out scavenging behaviour. Regardless, the perception that Andean bears are a significant threats to farmers’ livelihoods has resulted in organised efforts to reduce bear population levels via hunting and poisoning.

Farmers in Peru have enlisted the help of the military, local police and hunters to kill bears in an attempt to reduce crop raiding and attacks on livestock.

2008 conservation status

Andean bears are categorised as ‘VU’ (vulnerable) on the IUCN 2006 Red List, primarily as a result of habitat loss and unregulated hunting.


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