By LeeAnn Bies
Geographic Range
Tremarctos ornatus are the only bears to live in South America. Spectacled bears live along the slopes of the Andes mountains from Venezuela to Peru. Some have been found in eastern Panama and northern Argentina (Nowak, 1997; Ward and Kynaston, 1995).
Biogeographic Regions:
neotropical
(native
).
Habitat
(590.4 to 13776 ft)
Spectacled bears seem to prefer densely forested areas, especially humid forests between 1,900 and 2,350 meters. However, they have been reported from habitats as diverse as rain forest, cloud forest, dry forest, steppe lands, and coastal scrub desert (IBA, 1999; Ward and Kynaston, 1995; Nowak, 1997).
Terrestrial Biomes:
forest
; rainforest
; scrub forest
; mountains
.
Physical Description
(220 to 341 lbs; avg. 280.5 lbs)
(4.92 to 5.9 ft; avg. 5.41 ft)
Spectacled bears are small, shaggy, and black. They have yellow rings around the eyes and often a lighter colored, usually cream, muzzle, throat, and chest. The markings are variable and can extend to the throat in some, the chest in others, or be totally absent. The coat ranges from black, brown, or even reddish in color. This species gets in name from the circles around the eyes which make the bears appear as though they are wearing spectacles. Females are 30%-40% smaller than males. These bears have plantigrade feet, where both the heel and toe touch the ground as they walk. One unique characteristic of these bears is that they have 13 pairs of ribs while other bear species have 14 pairs. (IBA, 1999; Sanderson, 1972; Nowak, 1997; Ward and Kynaston, 1995; www.bears.org, 2001)
Some key physical features:
endothermic
; bilateral symmetry
.
Reproduction
April-June
Mating pairs usually stay together one or two weeks, copulating many times. While the female is in estrus, which only occurs for one to five days, the male and female go through a ritual of mock fighting and playing until the female is ready to mate (IBA, 1999).
Details of the reproductive behavior of spectacled bears in the wild are few. Mating usually takes place between April and June, and the litters are born between November and February. When the egg is fertilized, it divides a few times, and then floats freely in the uterus for several months. This is called delayed implantation, and it helps to ensure that the young are born when food is available. Gestation length in captivity is about 8 months. The litters range from one to three young. At birth, cubs are blind and weigh between 300-360 grams (Ward and Kynaston, 1995).
Key reproductive features:
iteroparous
; seasonal breeding
; gonochoric/gonochoristic/dioecious (sexes separate); sexual
; viviparous
; delayed implantation
.
Cubs are taken care of by their mothers, but grow quickly. After about a month cubs are able to go out with their mothers in search of food and after 6-8 months they can go off on their own (www.bears.org, 2001).
Parental investment:
altricial
; female parental care
.
Lifespan/Longevity
Lifespan in the wild is unknown, but in captivity T. ornatus can reach 20-25 years. One bear lived for 36 years and 5 months in captivity (Ward and Kynaston, 1995; Nowak, 1997; www.bears.org, 2001).
Behavior
Spectacled bears are primarily nocturnal and crepuscular. They sleep between or under large tree roots, on a tree trunk, or in a cave during the day. Their claws are specialized for climbing and they will spend days in trees. While in a tree, they sometimes make large platforms out of broken branches, which they use to reach fruit. These bears are not hibernators, probably because their food supply is available year round. They are timid and try to avoid humans (Nowak, 1997; www.bears.org, 2001)
Key behaviors:
nocturnal
; crepuscular
; motile
; solitary
.
Food Habits
For the most part T. ornatus is an omnivore (but almost exclusively vegetarian) with a preference for fruit, particularly those in the family Bromeliaceae. Plants in this family can make up as much as 50% of spectacled bears' diet. These bears climb large cacti to get to the fruit at the top. They also strip the bark off of trees to eat. These bears have been known to climb over 10 meters to gather food and are incredibly mobile traveling from tree to tree in search of food. They may stay in one fruit tree for 3 to 4 days awaiting the ripening period. They eat a variety of food, depending what is available in the season. Their diet includes berries, cacti, tree shrubs, honey, and sugarcane. If necessary these bears will eat small rodents, birds, or insects and will kill cattle if other food is not available. Roughly 4% of their diet is animal matter. Spectacled bears have extremely strong jaws allowing them to eat foods other animals cannot, such as tree bark and bromeliad hearts (Ward and Kynaston, 1995; IBA, 1999; Nowak, 1997; www.bears.org, 2001).
Animal Foods:
birds; mammals; insects.
Plant Foods:
wood, bark, or stems; fruit.
Ecosystem Roles
Spectacled bears are very important to the floral ecology of the forests they inhabit. They are also an important disperser of the tree seeds they consume (Ward and Kynaston, 1995).
Key ways these animals impact their ecosystem:
disperses seeds.
Economic Importance for Humans: Negative
South American farmers have persecuted these bears for attacking their livestock. Some bears have been known to kill a cow every day until they were killed. Farmers also consider the bears to be a threat to maize fields. Special pesticides are sprayed onto the fields to keep the bears away. Sometimes whole families of bears are destroyed by these poisons. The actual damage done from these bears may be overestimated and in reality is caused by birds and forest rodents (Ward and Kynaston, 1995).
Ways that these animals might be a problem for humans:
crop pest.
Economic Importance for Humans: Positive
These bears are hunted for their meat, fur, fat, grease, and bile. The meat is especially liked in northern Peru. The fat is said to cure rheumatism and arthritis (Ward and Kyanaston, 1995; Nowak, 1997;
Ways that people benefit from these animals:
food
.
Conservation Status
IUCN Red List: [link]:
Vulnerable.
US Federal List: [link]:
No special status.
CITES: [link]:
Appendix I.
It is estimated that there are fewer than 2,000 of these bears left in the wild. Habitat destruction and fragmentation due to agricultural growth are the biggest causes of these bears' decline. Hunting by sportsmen and landowners are also contributing factors, dating back to the 1800's, when the Spanish first arrived in South America. Poachers killed the bear because of the large market for bear paws, where one paw can bring in between $10 and $20 U.S. dollars. Around 1980 these bears were not thought to be in much danger because they are so adaptable, many using habitats people could not access. It has been discovered since then that surviving populations are fragmentary and restricted to isolated forests on mountainsides. Protection for spectacled bears is minimal. National parks of South America have a low budget and the government supports the settler farmers. Some farmers even have permission to use the land that is protected. Scientists are worried because inbreeding has started to occur in Peru, bringing about a decrease in adult size and the size of litters. Education of the local people is important to conservationists to get public support (www.bears.org, 2001; Nowak, 1997; Ward and Kynaston, 1995).
Other Comments
The spectacled bear is a direct descendant of a bear that was the largest predator in the Americas during the Ice Age. It was known as the Bulldog Bear (Arctodus simus). The spectacled bear is the only Tremarctine bear to survive into modern times. Today the spectacled bear is the largest carnivore found in South America.
Contributors
LeeAnn Bies (author), University of Michigan.
Cynthia Sims Parr (editor), University of Michigan.
