Bubalus depressicornisanoa

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Geographic Range

Bubalus depressicornis is found exclusively in the northern region of the Indonesian island of Celebes, which is also called Sulawesi. (Parker, 1990; Nowak, 1999; Anonymous, 2001; Massicot, 2001)

Habitat

The lowland anoa prefers undisturbed lowland forested areas and swamps. Shaded areas are preferred to escape from daytime temperatures. (Parker, 1990; Nowak, 1999; Anonymous, 2001)

Physical Description

Juvenile lowland anoas are covered with thick, wooly, yellowish brown hair. Adults are characterized by thick, black skin, and are only sparsely covered with brown to blackish hair. They also have white or yellowish-white hair on their forelegs, and sometimes on their throat and nape. Lowland anoas have a stocky body with the hindquarters slightly higher than the shoulders and a long tail averaging 40 cm in length. Adults stand at an average shoulder height of 86cm. The horns of an adult are triangular in section, flattened and wrinkled. The horns begin at the forehead and point diagonally backwards. Males have horns averaging 30cm in length, and females have horns that average 25cm in length. Anoas are very efficient at crashing through forest undergrowth, with the horns being held close to the back in order to avoid being tangled. (Parker, 1990; Huffman, 1999; Nowak, 1999; Anonymous, 2001; Massicot, 2001)

  • Range mass
    90 to 225 kg
    198.24 to 495.59 lb
  • Average length
    180 cm
    70.87 in

Reproduction

Lowland anoas are not known to have a breeding season. Both females and males become sexually mature at approximately 2 years of age. The female has a gestation period that lasts from 275 to 315 days. Females will usually go off alone during calving. Although a female can give birth to twins, typically only one offspring is born. Weaning occurs at a time period of 6 to 9 months after birth. Females typically reproduce annually. (Parker, 1990; Huffman, 1999; Nowak, 1999; Anonymous, 2001; Massicot, 2001)

  • Breeding season
    year round
  • Range number of offspring
    1 (low)
  • Average number of offspring
    1
  • Average number of offspring
    1
    AnAge
  • Range gestation period
    9.17 to 10.5 months
  • Range weaning age
    6 to 9 months
  • Average age at sexual or reproductive maturity (female)
    2 years
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    730 days
    AnAge
  • Average age at sexual or reproductive maturity (male)
    2 years
  • Average age at sexual or reproductive maturity (male)
    Sex: male
    730 days
    AnAge

Generally, exclusively the female cares for the young.

Lifespan/Longevity

Lowland anoas have been documented to live as long as 31 years in captivity. However, the maximum lifespan in the wild is approximately 20 years. (Jones, 1993; Anonymous 2001)

Behavior

Unlike all other wild cattle, lowland anoas are usually solitary. Mother and daughter pairs are common, and a few reports of small herds consisting of up to five individuals have been recorded. There is evidence that anoas are territorial, as males have been seen marking trees with their horns and scratching the soil after urinating. Lowland anoas are most active in the morning and afternoon, and frequently wallow in mud and water. Anoas typically move at the pace of a slow trot with an occasional clumsy leap. (Parker, 1990; Huffman, 1999; Nowak, 1999; Anonymous, 2001; Massicot, 2001)

Communication and Perception

Food Habits

Lowland anoas are herbivorous. Wild anoas are known to feed on aquatic plants, ferns, grasses, saplings, fallen fruit, palm, and ginger. In addition, they have been recorded to drink sea water which is thought to fulfill their mineral needs in areas that do not have salt licks or mineral spring water. Captive anoas are fed a diet of hay and herbivore pellets. (Parker, 1990; Nowak, 1999; Anonymous, 2001; Massicot, 2001)

  • Plant Foods
  • leaves
  • fruit

Predation

Adult lowland anoas do not have any predators (except humans). However, infant anoas are preyed upon by pythons (Python reticulatus or Python molurus) and the endemic civet (Macrogalidia musschembroekii). (Anonymous, 2001)

Ecosystem Roles

The lowland anoa controls forest understory growth by feeding on understory grasses and plants. (Parker, 1990; Huffman, 1999; Nowak, 1999; Anonymous, 2001; Massicot, 2001)

Economic Importance for Humans: Positive

Anoas are hunted because of their desirable meat which is still sold in local markets. In addition, the skull and

the horns are made into trophies or souvenirs. The horns have traditional value for medicinal purposes. Despite the fact that anoas are protected, local people still pursue illegal hunting not only in unprotected forests but also in conservation areas. Local hunters generally use snares, spears or dogs to kill anoas. (Melisch, 1995; Pangau, 2001)

Economic Importance for Humans: Negative

Wild lowland anoas can be very aggressive toward humans, especially young male anoas and female anoas with offspring. Several accounts of this species of anoa attacking humans with its sharp horns have been recorded. (Anonymous, 2001)

Conservation Status

The lowland anoa was widely distributed throughout northern Sulawesi in 1900. The several reasons for the drastic decline in the lowland anoa population include hunting and the expansion of settlement, which has resulted in logging activities, as well as clearing of forested areas and draining of marshland for agriculture. The current lowland anoa population is estimated to be approximately 5000 animals. The number of wild lowland anoas is still decreasing as illegal hunting continues and humans continue to populate its range. Ongoing research efforts by zoos, including the St. Louis Zoo, San Diego Zoo, Fort Worth Zoo and Woodland Park Zoo in Seattle, Washington, continue to support a captive breeding program for lowland anoas. As of 1995, 110 Bubalus depressicornis were in captivity. (O'Brien and Kinnaird, 1996; Huffman, 1999; Anonymous, 2001; Massicot, 2001; Pangau, 2001)

Other Comments

Several lowland anoa fatalities have occured in zoos as a result of attempts to keep these solitary animals in pairs or groups; typically the larger animals have disembowelled their counterparts with their horns. (Huffman, 1999)

Contributors

David Miller (author), University of Michigan-Ann Arbor, Kate Teeter (editor), University of Michigan-Ann Arbor.

Glossary

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

drug

a substance used for the diagnosis, cure, mitigation, treatment, or prevention of disease

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

female parental care

parental care is carried out by females

fertilization

union of egg and spermatozoan

folivore

an animal that mainly eats leaves.

food

A substance that provides both nutrients and energy to a living thing.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

frugivore

an animal that mainly eats fruit

herbivore

An animal that eats mainly plants or parts of plants.

internal fertilization

fertilization takes place within the female's body

island endemic

animals that live only on an island or set of islands.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oriental

found in the oriental region of the world. In other words, India and southeast Asia.

World Map

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

social

associates with others of its species; forms social groups.

solitary

lives alone

swamp

a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.

tactile

uses touch to communicate

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

year-round breeding

breeding takes place throughout the year

References

Anonymous, 1/1/2001. "Lowland Anoa" (On-line). Accessed 11/18/2001 at http://www.zoo.org/educate/fact_sheets/anoa/anoa.htm.

Huffman, B. 1/1/1999. "Lowland Anoa" (On-line). Accessed 11/18/2001 at http://www.ultimateungulate.com/anoalwlnd.html.

Jones, M. 1993. Longevity of ungulates in captivity. Int. Zoo Yb., 32: 159-169.

Massicot, P. 9/12/2001. "Animal Info-Lowland Anoa" (On-line). Accessed 11/18/2001 at http://www.animalinfo.org/species/artiperi/anoadepr.htm.

Melisch, R. 1995. Anoa threatened by souvenir trade in south Sulawesi, Indonesia. Oryx, 29: 224-225.

Nowak, R. 1999. Walker's Mammals of the World. Baltimore: The John Hopkin's University Press.

O'Brien, T., M. Kinnaird. 1996. Changing populations of birds and mammals in north Sulawesi. Oryx, 30: 150-156.

Pangau, M. 1/1/2001. "DISTRIBUTION AND FACT FINDINGS OF THE ANOA" (On-line). Accessed 11/18/2001 at http://www.gwdg.de/~cetsaf/absolventen/p3/mpangau.htm.

Parker, S. 1990. Grzimek's Encyclopedia of Mammals. New York: McGraw Hill Publishing Company.