Tremarctos ornatus is the only species of bear native to South America. It can be found throughout mountainous regions of the Andes in Ecuador, Colombia, Venezuela, Peru, Bolivia, and might also occur in northwestern Argentina and into Panama (Hunter, 2011).
Biogeographic Regions: neotropical (Native )
- Hunter, L. 2011. Carnivores of the World. New Jersey, USA: Princeton University Press.
- Nowak, R. 1999. Walker's Mammals of the World. Baltimore, MD: Johns Hopkins University Press.
Historical reports include the Panama regions of El Darien (Jorgenson 1984) and Caledonia (Global Biodiversity Information Facility Data Portal 2008) but recent surveys of suspected populations in El Darien (Goldstein et al. 2007), as well as in northern Argentina, have not yielded conclusive evidence of bear presence.
Spectacled bears are medium sized bears that are typically uniformly black in color, but reddish-brown individuals have been observed. The common name "spectacled bears" comes from the white or tan markings on the face that create rings around the eyes; these lighter markings often extend down the chest, forming a bib-like patch of light fur. The lighter markings are highly variable, unique to each individual, and may be absent altogether. The coat is of medium to long length. Spectacled bears have a short tail, about 70mm long, that is often completely hidden by the fur. They have a stocky build, small round ears, a thick short neck, and a stout muzzle. Like all bears, spectacled bears are equipped with a plantigrade stance and the front limbs are longer than their hind limbs. This feature of the limbs gives most bears amazing climbing abilities. Relative to their body size, spectacled bears have the largest zygomaticomandibularis muscle of any bear species. This musculature feature, along with the blunt lophs of the cheek teeth are adaptations for their primarily herbivorous diet.
Range mass: 60 to 200 kg.
Range length: 1.3 to 2.0 m.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: male larger
Spectacled bears inhabit a wide variety of habitats throughout their range. They are most commonly found in dense cloud forests where there is an abundance of food and shelter. They are also found in paramo, scrub forest and grasslands. It is believed that these bears travel between habitat types depending on the season, but the timing of these migrations and what drives them is unknown. They are found from 475 to 3658 meters elevation, mostly between 1900 and 2350 meters.
Range elevation: 475 to 3,658 m.
Average elevation: 1900-2350 m.
Habitat Regions: tropical ; terrestrial
Terrestrial Biomes: savanna or grassland ; forest ; rainforest ; scrub forest ; mountains
Kattan, G., H. Hernández, I. Goldstein, V. Rojas, O. Murillo, C. Gómez, . Restrepo, F. Cuesta. 2004.
Range fragmentation in the spectacled bear Tremarctos ornatus in the northern Ande. Oryx, 38: 155-163. Accessed March 15, 2012 at http://journals.cambridge.org.proxy1.cl.msu.edu/action/displayAbstract?fromPage=online&aid=220197.
- Servheen, C., S. Herrero, B. Peyton. 1999. Bears. Status Survey and Conservation Action Plan. Gland, Switzerland and Cambridge, UK: IUCN.
Habitat and Ecology
With the notable exception of the dry forest-scrub habitat in north coastal Peru (Peyton 1999b), Andean bears are most commonly found in high elevation elfin forests, upper montane humid forest, and humid grasslands (Peyton 1987a,b, Velez 1999, Cuesta et al. 2003, Rios-Uzeda et al. 2005). Within this range, habitat preferences are uncertain. In portions of the central Andes in Bolivia, Andean bears were reported to select wet montane / foothill forests at lower elevations (Rumiz et al. 1999); elsewhere in Bolivia they heavily used cloud forests of the upper slopes of the Andes and rarely used dry montane forests (Rios-Uzeda et al. 2005). Bear presence can readily be identified in the high altitude grasslands due to the easier visibility and the durability of the obvious feeding sign, but these grasslands may not sustain bears year-round without access to forest (Suarez 1985, Paisley 2001).
Andean bears are omnivores, feeding mainly on vegetative material such as fruits and succulent plants, and occasionally meat. Common dietary mainstays throughout their distribution are the succulent parts of plants of the families Bromeliaceae and Arecaceae (Peyton 1980, Suarez 1988, Mondolfi 1989). However, food habits change from site to site and even within sites depending on the availability of particular resources. Tree and ground nests are used for resting where Andean bears feed on fruits high in the tree canopy and at sites where bears consume animal (e.g., livestock) carcasses (Goldstein 1991, Velez 1999). Activity patterns range from strictly diurnal for wild bears in Bolivia (Paisley and Garshelis 2006a) to mixed diurnal and nocturnal for reintroduced bears in Ecuador (Castellanos et al. 2005). As food is available year-round in all parts of their range, Andean bears do not hibernate. Based on the first few individuals of this species to be monitored using ground telemetry in Bolivia (Paisley and Garshelis 2006b) and Ecuador (Castellanos 2007 and pers. com. 2008), home ranges overlap to a high degree and minimum home range sizes vary from 10 to 160 km² (although these are underestimates, as the bears were regularly out of range of radiotelemetry in both studies).
Information on reproduction in this species is limited. Litter size is typically two cubs. The timing of births in the wild has rarely been observed, but in captivity birthing varies with latitude (Garshelis 2004). Presumed mating pairs have been observed in the wild during March-October.
Besides giant pandas, spectacled bears are probably the most herbivorous bear species. They seem to have a strong preference for bromeliads and fruits, but have also been observed eating moss, cacti, orchids, bamboo, honey, tree wood, palms, invertebrates, small mammals, birds, and insects. Spectacled bears have been known to raid farmers crops, especially maize, which often results in the bears being shot. They have rarely been observed killing livestock and will readily scavenge from a carcass. One of their more unique feeding techniques is the construction and use of feeding platforms to obtain easier access to food high in the canopy.
Animal Foods: birds; mammals; carrion ; insects
Plant Foods: leaves; wood, bark, or stems; seeds, grains, and nuts; fruit; flowers; bryophytes
Primary Diet: herbivore (Folivore , Frugivore )
The roll that spectacled bears play in the ecosystem remains largely unstudied. However, because of their largely herbivorous diet it is likely that they play a role in seed dispersal.
Ecosystem Impact: disperses seeds
Spectacled bears are one of the largest mammals in South America and there are no reported predators on adult bears. Spectacled bear cubs may be preyed on by mountain lions, jaguars, and occasionally by adult male spectacled bears.
- mountain lions (Puma concolor)
- jaguars (Panthera onca)
- spectacled bears (Tremarctos ornatus)
Known prey organisms
This list may not be complete but is based on published studies.
Life History and Behavior
Olfaction is the dominant form of communication for spectacled bears. At least five distinct vocal communication sounds used between mothers and cubs have been described.
Communication Channels: visual ; acoustic ; chemical
Perception Channels: visual ; tactile ; chemical
The longest recorded life span of a spectacled bear was at the National Zoo in Washington D.C., where the bear lived to be 36 years, 8 months of age. Not much is known about the average lifespan of a wild bear, but it is believed to be around 20 years.
Status: captivity: 36.7 (high) years.
Status: wild: 20 years.
Status: captivity: 25.0 years.
Status: captivity: 36.4 years.
- Paisley, S. 2008. "IUCN" (On-line). Accessed March 14, 2012 at http://www.iucnredlist.org/apps/redlist/details/22066/0.
Lifespan, longevity, and ageing
Much of the mating behavior of this species remains unstudied. Males and females come together to mate between the months of April and June. The pair remains together for 1 to 2 weeks, copulating several times during this period.
Mating System: polygynous
Mating pairs of spectacled bears have been seen together between March and October, during the time of year when fruit is beginning to ripen. This indicates that, like bears in captivity, spectacled bears are probably adapted to breeding at various times throughout the year. Spectacled bears are monestrous and are probably capable of delayed implantation. This would explain the variation in gestation times in captive bears, 160 to 255 days, and the "out of season" births observed in wild bears. Cubs are typically born several months before the fruit season begins, this allows the cubs sufficient time to be weaned before the fruit ripens for them to eat. In the wild, 1 to 4 cubs are born to a single female. The cubs are born with their eyes closed and weigh about 300 g each. The size of the litter is positively correlated with the weight of the female and the abundance and variety of food sources. In captive bears, a female gives birth to two cubs on average. Both male and female bears reach sexual maturity between the ages of 4 and 6.
Breeding interval: Spectacled bears breed once a year
Breeding season: Spectacled bears breed between March and October.
Range number of offspring: 1 to 4.
Average number of offspring: 2.
Range gestation period: 5.5 to 8.5 months.
Average time to independence: 1 years.
Range age at sexual or reproductive maturity (female): 4 to 7 years.
Range age at sexual or reproductive maturity (male): 4 to 7 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous ; delayed implantation
Average birth mass: 320 g.
Average number of offspring: 1.5.
Spectacled bear cubs stay with their mother for up to a year after birth. The cubs are born blind and their eyes do not open until 30 days, during which time they are completely dependent on their mother. There is no known paternal involvement in the rearing of the cubs and males may eat any cubs they come into contact with.
Parental Investment: altricial ; female parental care ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Provisioning: Female, Protecting: Female); extended period of juvenile learning
- 1999. "International Association for Bear Research and Management" (On-line). Bear Species Descriptions. Accessed April 16, 2012 at http://www.bearbiology.com/index.php?id=42.
- Hunter, L. 2011. Carnivores of the World. New Jersey, USA: Princeton University Press.
- Nowak, R. 1999. Walker's Mammals of the World. Baltimore, MD: Johns Hopkins University Press.
- Servheen, C., S. Herrero, B. Peyton. 1999. Bears. Status Survey and Conservation Action Plan. Gland, Switzerland and Cambridge, UK: IUCN.
Molecular Biology and Genetics
Barcode data: Tremarctos ornatus
Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.
See the BOLD taxonomy browser for more complete information about this specimen and other sequences.
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Download FASTA File
Statistics of barcoding coverage: Tremarctos ornatus
Public Records: 2
Specimens with Barcodes: 3
Species With Barcodes: 1
As with many species, loss of habitat plays a major role in the population decline of spectacled bears. In Ecuador alone there has been an estimated 40% loss of suitable habitat in the bears natural range. This creates small isolated island populations of bears. Since spectacled bears rely on different habitats to produce their food supply during different seasons, it is essential to preserve large areas to ensure that the bears have a sufficient supply of food throughout the year.
US Federal List: no special status
CITES: appendix i
IUCN Red List of Threatened Species: vulnerable
- Peralvo, M., F. Cuesta, F. van Manen. 2005. Delineating Priority Habitat Areas for the Conservation of Andean Bears in Northern Ecuador. Ursidae, 16: 222-233.
IUCN Red List Assessment
Red List Category
Red List Criteria
Based just on trends in human population density (and the deterioration of habitat and increased exploitation of animal populations that this inevitably entails), Cardillo et al. (2004) listed Andean bears among the Carnivores that are most likely to move toward extinction. By 2030, they predict that this species would meet the IUCN criteria for Endangered.
- 1994Vulnerable(Groombridge 1994)
- 1990Vulnerable(IUCN 1990)
- 1988Vulnerable(IUCN Conservation Monitoring Centre 1988)
- 1986Vulnerable(IUCN Conservation Monitoring Centre 1986)
- 1982Vulnerable(Thornback and Jenkins 1982)
Many Andean bear populations are isolated in small to medium-sized patches of intact habitat, particularly in the northern part of the range (Yerena et al. 2003, Kattan et al. 2004). The situation tends to improve towards the southern range, with some large patches of wilderness still remaining (Peyton 1999a). Nevertheless, human population growth and national development plans throughout the Tropical Andes continue to be an important cause of habitat fragmentation and to threaten the connectivity among remaining wilderness patches.
Poaching is a serious threat throughout the Andean bear range. Bears are often killed after damaging crops, particularly maize, or after purportedly killing livestock (Goldstein 1991, Peyton 1999b, Rumiz and Salazar 1999, Suarez 1999, Castellanos 2002, Morales 2003). Also, Andean bear products are used for medicinal or ritual purposes and at some localities Andean bear meat is highly prized (Yerena 1999). Live bears are also sometimes captured and sold (Jorgenson and Sandoval 2005). Human induced mortality endangers the viability of small remnant populations.
Lack of knowledge about the distribution and status is a problem throughout the region. In many areas, information about the status of Andean bears is outdated or, particularly in the southern portion of the range, simply non-existent. The absence of knowledge makes it difficult to develop realistic management plans for the conservation of this species, or to monitor changes in its distribution (reflective of changes in population status).
Studies on the distribution, frequency and intensity of Andean bear-human conflicts have been carried out in some areas in order to better understand these situations and thereby develop management measures to reduce conflicts and the consequent killing of bears (Goldstein et al. 2006). Management plans to reduce bear-cattle conflicts have been developed at the Oyacachi, Ecuador, based on predation probability models (Goldstein 2006).
Workshops have been conducted in several of the range countries to train researchers and personnel from national parks on survey techniques, development of habitat models, and general knowledge about the ecology, distribution and status of the species (Goldstein 2006).
Andean bears are listed on Appendix I of CITES and are protected through national legislation in each range country. However, there are loopholes in these laws by which bears can be (and thus frequently are) killed or removed from the wild (Orejuela and Jorgenson 1999, Peyton 1999b, Rumiz and Salazar 1999, Suarez 1999, Yerena 1999, Jorgenson and Sandoval 2005).
Relevance to Humans and Ecosystems
Spectacled bears may gather in small groups to feed in corn fields. They may rarely steal livestock from local farms that are encroaching on their habitat.
Negative Impacts: crop pest
Spectacled bears possess great religious and cultural value to the native people who share their range. Spectacled bears are sometimes hunted illegally for medicinal or ritual purposes. In some parts of their range the meat is highly prized. The gallbladder is often sold to the east Asian market, where it is used for traditional medicinal purposes, although there is no proven benefit of these materials for humans and the effect of this illegal hunting on populations can be devastating.
Positive Impacts: food ; ecotourism
- Ruiz-Garcia, B., H. Gómez, R. Wallace. 2006. Habitat preferences of the Andean bear (Tremarctos ornatus) in the Bolivian Andes. Journal of Zoology, 268: 271-278.
The spectacled bear (Tremarctos ornatus), also known as the Andean bear or Andean short-faced bear and locally as jukumari (Aymara), ukumari (Quechua) or ukuku, is the last remaining short-faced bear (subfamily Tremarctinae) and its closest relatives are the extinct Florida spectacled bear, and the giant short-faced bears of the Middle Pleistocene to Late Pleistocene age. Spectacled bears are the only surviving species of bear native to South America, and the only surviving member of the subfamily Tremarctinae.
The spectacled bear is the only bear native to South America and is technically the largest land carnivore on that continent, although as little as 5% of its diet is composed of meat. South America's largest obligate carnivorous mammal is the jaguar (Panthera onca). Among South America's extant, native land animals, only the Baird's (Tapirus bairdii) and South American tapirs (T. terrestris) are heavier than this species. The spectacled bear is a mid-sized species of bear. Overall, its fur is blackish in color, though bears may vary from jet black to dark brown and to even a reddish hue. The species typically has distinctive beige or ginger-coloured markings across its face and upper chest, though not all spectacled bears have "spectacle" markings. The pattern and extent of pale markings are slightly different on each individual bear, and bears can be readily distinguished by this. Males are a third larger than females in dimensions and sometimes twice their weight. Males can weigh from 100 to 200 kg (220 to 440 lb), and females can weigh from 35 to 82 kg (77 to 181 lb). Head-and-body length can range from 120 to 200 cm (47–79 in), though mature males do not measure less than 150 cm (59 in). The tail is a mere 7 cm (2.8 in) in length, and the shoulder height is from 60 to 90 cm (24–30 in). Compared to other living bears, this species has a more rounded face with a relatively short and broad snout. In some extinct species of the Tremarctinae subfamily, this facial structure has been thought to be an adaptation to a largely carnivorous diet, despite the modern spectacled bears' herbivorous dietary preferences.
Distribution and habitat
Despite some rare spilling over into eastern Panama, spectacled bears are mostly restricted to certain areas of northern and western South America. They can range in western Venezuela, Colombia, Ecuador, Peru, western Bolivia, and northwestern Argentina. The species is found almost entirely in the Andes Mountains. Before spectacled bear populations became fragmented during the last 500 years, the species had a reputation for being adaptable, as it is found in a wide variety of habitats and altitudes throughout its range, including cloud forests, high-altitude grasslands, dry forests and scrub deserts. A single spectacled bear population on the border of Peru and Ecuador inhabited as great a range of habitat types as the world's brown bears (Ursus arctos) now occupy. The best habitats for spectacled bears are humid to very humid montane forests. These cloud forests typically occupy a 500 to 1,000 m (1,600 to 3,300 ft) elevational band between 1,000 and 2,700 m (3,300 and 8,900 ft) depending on latitude. Generally, the wetter these forests are the more food species there are that can support bears. Occasionally, they may reach altitudes as low as 250 m (820 ft), but are not typically found below 1,900 m (6,200 ft) in the foothills. They can even range up to the mountain snow line at over 5,000 m (16,000 ft) in elevation.
Naming and etymology
Tremarctos ornatus is commonly referred to in English as the "spectacled bear", a reference to the light colouring on its chest, neck and face, which may resemble eyeglasses in some individuals, or the "Andean bear" for its distribution along the Andes.
The root trem- comes from a Greek word meaning "hole;" arctos is the Greek word for "bear." Tremarctos is a reference to an unusual hole on the animal's humerus. Ornatus, Latin for "decorated", is a reference to the markings that give the bear its common English name.
Behavior and diet
Spectacled bears are one of the half of extant bear species that are habitually arboreal, alongside the American (Ursus americanus) and Asian black bears (U. thibetanus) and the sun bears (Helarctos malayanus). In Andean cloud forests, spectacled bears may be active both during the day and night, but in Peruvian desert are reported to bed down under vegetative cover during the day. Their continued survival alongside humans has depended mostly on their ability to climb even the tallest trees of the Andes. They usually retreat from the presence of humans, often by climbing trees. Once up a tree, they may often build a platform, perhaps to aid in concealment, as well as to rest and store food on. Although spectacled bears are solitary and tend to isolate themselves from one another to avoid competition, they are not territorial. They have even been recorded to feed in small groups at abundant food sources. Males are reported to have an average home range of 23 km2 (8.9 sq mi) during the wet season and 27 km2 (10 sq mi) during the dry season. Females are reported to have an average home range of 10 km2 (3.9 sq mi) in the wet season and 7 km2 (2.7 sq mi) in the dry season. When encountered by humans or other spectacled bears, they will react in a docile but cautious manner, unless the intruder is seen as a threat or a mother's cubs are endangered. Like other bears, mothers are protective of their young and have attacked poachers. There is only a single reported human death due to a spectacled bear, which occurred while it was being hunted and was already shot. The only predators of cubs include cougars (Puma concolor) and possibly male spectacled bears. The bears "appear to avoid" jaguars, but the jaguar has considerably different habitat preferences, does not overlap with the spectacled bear in altitude on any specific mountain slope, and only overlaps slightly (900m) in altitude if the entire Cordillera Oriental is considered based upon unpublished data. Generally, the only threat against adult bears is humans. The longest-lived captive bear, at the National Zoo in Washington, DC, attained a lifespan of 36 years and 8 months. Lifespan in the wild has not been studied, but bears are believed to commonly live to 20 years or more unless they run afoul of humans.
Spectacled bears are more herbivorous than most other bears; normally about 5 to 7% of their diets is meat. The most common foods for these bears include cactus, bromeliads (especially Puya ssp., Tillandsia ssp. and Guzmania ssp.) palm nuts, bamboo hearts, frailejon (Espeletia spp.), orchid bulbs, fallen fruit on the forest floor, and unopened palm leaves. They will also peel back tree bark to eat the nutritious second layer. Much of this vegetation is very tough to open or digest for most animals, and the bear is one of the few species in its range to exploit these food sources. The spectacled bear has the largest zygomatic mandibular muscles relative to its body size and the shortest muzzle of any living bear, slightly surpassing the relative size of the giant panda's (Ailuropoda melanoleuca) morphology here. Not coincidentally, both species are known for extensively consuming tough, fiberous plants. Unlike the ursid bears whose fourth premolar has a more well-developed protoconid, an adaptation for shearing flesh, the fourth premolar of spectacled bears has blunt lophs has three pulp cavities instead of two, and can have three roots instead of the two that characterize ursid bears. The musculature and tooth characteristics are designed to support the stresses of grinding and crushing vegetation. Besides the giant panda, the spectacled bear is perhaps the most herbivorous living bear species. These bears also eat cultivated plants, such as sugarcane (Saccharum ssp.), honey (made by Apis ssp.), and corn (Zea mays), and have been known to travel above the tree line for berries and more ground-based bromeliads. When food is abundant, such as large corn fields, up to nine individual bears have fed close by each other in a single vicinity. Animal prey is usually quite small, but these bears can prey on adult deer, llama (Lama glama) and domestic cattle (Bos primigenius taurus) and horses (Equus ferus caballus). Animal prey has included rabbits, mice, other rodents, birds at the nest (especially ground-nesting birds like tinamous or lapwings (Vanellus ssp.)), arthropods, and carrion. They are occasionally accused of killing livestock, especially cattle, and raiding corn fields. Allegedly, some bears become habituated to eating cattle, but the bears are actually more likely to eat cattle as carrion and some farmers may accidentally assume the spectacled bear killed them. Due to fear of loss of stock, bears may be killed on sight.
Mating may occur at almost any time of the year, but activity normally peaks in April and June, at the beginning of the wet season and corresponding with the peak of fruit-ripening. The mating pair are together for one to two weeks, during which they will copulate multiple times. Births usually occur in the dry season, between December and February. The gestation period is 5.5 to 8.5 months. From one to three cubs may be born, with four being rare and two being the average. The cubs are born with their eyes closed and weigh about 300 to 330 g (11 to 12 oz) each. Although this species does not give birth during the hibernation cycle as do northern bear species, births usually occur in a small den and the female waits until the cubs can see and walk before she leaves with them. The size of the litter has been positively correlated with both the weight of the female and the abundance and variety of food sources, particularly the degree to which fruiting is temporally predictable. The cubs often stay with the female for one year before striking out on their own. Breeding maturity is estimated to be reached at between four and seven years of age for both sexes, based solely on captive bears.
The spectacled bear population is under threat for a number of reasons. Unfortunately, still no species-level conservation efforts are known to exist for spectacled bears. Each government has made differing commitments to conservation in this species range, with Venezuela, thanks to its relatively high level of scientific industry and relatively stable economy being the most advanced at bear conservation to Colombia, where the species and its habitats are largely unprotected. The bears are hunted by locals due to a belief they will eat livestock (although spectacled bears do not normally eat large quantities of meat). Their gall bladders are also valued in traditional Chinese medicine and can fetch a high price on the international market. Perhaps the most epidemic problem for the species is extensive logging and farming, which has led to habitat loss for the largely tree-dependent bears. As little of 5% of the original habitat in Andean cloud forest remains. As the bear's food sources have been disappearing, it relies on crops for food. So, farmers see the bears as competition and hunt them. Legislation against hunting the bears exists, but is rarely enforced. The IUCN has recommended the following courses for spectacled bear conservation: expansion and implementation of conservation land to prevent further development, greater species level research and monitoring of trends and threats, more concerted management of current conservation areas, stewardship programs for bears which engage local residents and the education of the public regarding spectacled bears, especially the benefits of conserving the species due to its effect on natural resources.
In the documentary Paddington Bear: The Early Years, British actor Stephen Fry encounters a spectacled bear called Yogi, which was kept in a small cage by Andean villagers (see also Paddington Bear). Fry bartered with the villagers to have the bear released, and it was taken to an enclosure in Machu Picchu. Fry's interest in the bears led to the follow-up documentary, Stephen Fry and the Spectacled Bears, and he also wrote and published his experiences in Rescuing the Spectacled Bear: A Peruvian Diary.
In the BBC television programme Serious Andes, a team of eight teenagers built a prerelease enclosure for two spectacled bears before returning them to the wild. The BBC documentary "Spectacled Bears: Shadows of the Forest" looks at some of the bear research being done in Peru and Ecuador and what the researchers are discovering.
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