The spectacled bear of today can be found only in the Andes mountain range of South America from Venezuela to Argentina at 600 to 14,000 feet. The lowlands where the bears were once abundant were seized long ago for agricultural use. The bears are much more numerous on the eastern side of the Andes, where they are less vulnerable to human colonization. Being arboreal creatures, they prefer densely humid forests, and spend a good amount of their time in trees where they build platforms for feeding and sleeping. Though they are non-territorial, they tend to be reclusive and avoid one another except when mating or raising offspring.
The spectacled bear is one of the largest mammals in South America, second only to the tapir. On average, the spectacled bear measures 5 to 6 feet in length and stands about 30 inches high when on all 4. They usually weigh about 175 to 275 pounds, though they have been known to weigh over 400 pounds. Females (sows) are 30% to 40% smaller than males (boars).
Their fur is usually black, though occasionally some are seen having a brownish or reddish tone. The fur covering their face, nose, throat, and sometimes chest is a creamy-white color. Within the light fur on their face, they have brownish-black circles around their eyes, making it look as if they are wearing spectacles. Hence its name. However, the amount and pattern of their light fur can vary to the extreme. Because of the warm climate where they live, their fur is reasonable thinner than most other bear species. Also, because of the climate, there is no need for them to hibernate.
Spectacled bears have long claws which help them in both climbing and digging for food. Because of their semi-short legs, they are capable of slipping under dense vegetation and going many places inaccessible to many creatures. Spectacled bears have little reason to be vocal when they are alone which is most of the time. However, when they occasionally encounter other creatures, they can be very verbal.
Though the spectacled bear is an omnivorous animal, it is more of a vegetarian than any other bear. Because of their large flat molars they are able to chew up a number of things too tough for any other animals to eat such as cactus, palm nuts, orchid pseudobulbs, and unopened palm leaves. They spend most of the year between low jungle forests and high cloud forests where the fruit trees are. They also feed on sugarcane, corn, and honey and occasionally will travel above the tree line to find berries and bromeliad.
On average, 5% to 7% of the spectacled bear's diet is made up of animals such as rabbits, mice, birds, llamas, and domestic cattle. They are often killed by farmers when they get into the habit of feeding on cattle.
Breeding season is usually in the spring from April through June. During this time, the bears usually stay together in pairs for a couple weeks, frequently copulating. Females are capable of planning their pregnancy and labor to make sure their food supply is ample at the time they give birth which is usually about a 90 days prior to the peak of the fruit season.
They usually begin to reproduce somewhere between the age of 4 and 7. Gestation periods can vary anywhere from 5 1/2 to 8 months. Like with most other bears, the pregnancy of the spectacled bear can have delayed implantation where the fertilized ovum floats in the uterus for a period of time before attaching to the wall of the uterus and continuing to develop. If there is a season when food is extremely scarce, the embryos can simply be absorbed into the mother's body and she will not give birth that year.
The mother will build a den just prior to giving birth. Usually, 1 or 2 cubs are born from November through February. They weigh 10 to 18 ounces at birth and their eyes remain closed for the first month. The cubs stay with their mother for 6 to 8 months.
Spectacled bears have lived up 36 years in zoos. However, their longevity in the wild is thought to be closer to 25 years. There is believed to be fewer than 2,000 spectacled bears in the wild. Because of continuous human settlement causing isolation and fragmentation of the bear's population, widespread inbreeding problems have been seen, affecting the genetic vitality of the bear's species. They are listed as vulnerable on the World Conservation Union's Red List of Threatened Species.