Dendrolagus matschieiHuon tree kangaroo

Geographic Range

Dendrolagus matschiei is found exclusively in the Huon Peninsula of Papau New Guinea and the nearby island of Umboi, where they were probably introduced by humans. It is the only tree kangaroo species that inhabits this area. (Flannery 1995, Wilson 1993)

Habitat

Dendrolagus matschiei is found in lower montane forests at elevations of 1000 to 3000 meters. Oaks are the predominant tree species at the lower elevations while conifers are common at the higher elevations. Tree ferns and epiphytes are common and there is a large accumulation of leaf litter. (Flannery 1995, Moeller 1990)

  • Range elevation
    1000 to 3000 m
    3280.84 to 9842.52 ft

Physical Description

Tree kangaroos are similar in form to their ground dwelling relatives but have many adaptations specific to their arboreal existance. They have stocky bodies with forelimbs and hindlimbs closer in proportion than other macropods. Body length ranges from 55 to 63 cm. Their tails are long, equivalent to body length, and cylindrical rather than tapered and used for balancing. They have thick fur that grows in an opposite direction on their nape and back, enabling them to easily shed water when crouched in their typical position with head lower than shoulders. The female has a well-developed pouch with four mammae.

Dendrolagus matschiei are chestnut to red brown with a bright yellow tail, belly, ear edges, and feet. Their faces are yellow and white. They often have a dark stripe down their back and a vortex of fur in the middle of their back. They have cushion-like pads on their feet covered with roughened skin, and some of their nails are curved.

Dendrolagus matschiei can be distinguished from the closely related D. goodfellowi (once considered a subspecies) by the absence of golden back stripes, solidly colored yellow tail and more sombre coloration. Dendrolagus matschiei have shorter feet than other tree kangaroos and have larger ears. They have a diastema between their third incisor and canine of 2.95 +- 0.8 mm. The interparietal bone is large with an acute apex.

(Nowak 1991, Moeller 1990, Flannery 1995, Groves 1982)

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    6 to 13 kg
    13.22 to 28.63 lb
  • Range length
    55 to 63 cm
    21.65 to 24.80 in
  • Average basal metabolic rate
    7.96 W
    AnAge

Reproduction

During estrous, the female descends to the ground and approaches the male. This contact is followed by tongue-clicking, hissing and swatting of the male, but the female usually allows the male to mount within ten minutes. Copulation lasts up to an hour and generally takes place on the ground. Often a semen plug is found.

Female D. matschiei are polyestrous with no defined breeding season, although low copulation rates have been recorded from October through March in captivity. Estrous occurs every 51-79 days. Delayed implantation does not occur in D. matschiei (but has been recorded in other Dendrolagus species) nor is there any embryonic diapause. Gestation lasts 39-45 days, the longest recorded gestation period for any marsupial. Twenty four to 48 hours prior to birth, the female isolates herself. When parturition is close, she assumes the birth position by sitting on the base of her tail with her tail between her legs. It takes approximately 2 minutes for the tiny (less than 1 inch) joey to crawl up and into the pouch. Cleaning of the pouch is usually noted right after birth, often with the female's entire head in the pouch.

The joey firmly attaches to one of four nipples for 90-100 days after birth. At 250 days old, the joey first looks out of the pouch and begins to take notice of the mother's diet. At 300 days, the joey first ventures out of the pouch and at 350 days permanently vacates the pouch. Tree kangaroo joeys have a long pouch life in comparison to other macropods, e.g. red kangaroos permanently exit the pouch at 235 days.

Tree kangaroos reach sexual maturity at two years old and are reproductive for 10-12 years.

(Flannery 1990, Collins 1990)

  • Breeding interval
    Interbirth interval is determined by the nutritional status of the mother.
  • Breeding season
    Breeding can occur throughout the year.
  • Average number of offspring
    1
  • Average number of offspring
    1
    AnAge
  • Range gestation period
    39 to 45 days
  • Average weaning age
    12 months
  • Average time to independence
    12 months
  • Average age at sexual or reproductive maturity (female)
    2 years
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    845 days
    AnAge
  • Average age at sexual or reproductive maturity (male)
    2 years

Females care for and nurse their young for extended periods of time.

Lifespan/Longevity

Captive D. matschiei have lived as long as 14 years.

Behavior

Tree kangaroos are very agile in trees and can travel rapidly from tree to tree, leaping as much as 9 meters down to an adjoining tree. They are good climbers but more awkward than other tree kangaroo species. When climbing, tree kangaroos spring up 2-3 feet, wrap their arms around the tree, place their feet pointing up against the tree and scale the trunk with arms sliding and feet hopping. Tree kangaroos always back down trees, unlike opossums which can go down head first. They frequently descend to the ground by leaping. The tail, which is arched upward, serves as a counterbalance. They can jump down as much as 18 meters without injury. They move on the ground with a hobbling gait and can speed up by hopping to 4.8 km/hr. Despite their climbing and jumping abilities, tree kangaroos sleep 60% of the time, curling up in whatever tree they happen to be in. Dendrolagus matschiei are solitary (except during breeding) and tend to ignore one another even when sharing the same tree. Females do not share territories. Territory size of females averages 4.5 acres, while males claim overlapping territories of 11 acres. Larger territories increase breeding opportunities for males.

(Nowak 1991, Moeller 1990, Flannery 1995, Procter-Gray 1990)

Communication and Perception

Matschiei's tree kangaroos use their vision, touch, smell, and hearing to perceive their environment. Communication occurs by visual display, touch, some vocalization, and, most importantly, through chemical cues.

Food Habits

Dendrolagus matschiei are almost exclusively folivorous and prefer mature leaves. Although D. matschiei retain the large fermentation chamber stomachs characteristic of the macropod family, their basal metabolic rate is only 70% that of the grass eating red kangaroo, possibly an adaptation to a diet of leaves which tend to contain more toxins than fruit or grasses. Tree kangaroos eat sporadically throughout the day for an average of 15-20 minutes every four hours. The remainder of their diet consists of wild fruits, flowers, nuts, insects, bark, sap, bird eggs, and young birds. In captivity, D. matschiei are fed a high fiber diet of leaves, fruits and vegetables. Because large quantities of fresh leaves which are high in tannin are not easily obtained by most zoos, the diet is usually supplemented with tea leaves. Without the supplement, captive tree kangaroos tend to lose the rich color of their coats. Hard-boiled eggs and occasional chicks are also offered.

(Proter-Gray 1990, Collins 1990)

  • Animal Foods
  • birds
  • eggs
  • insects
  • Plant Foods
  • leaves
  • roots and tubers
  • wood, bark, or stems
  • seeds, grains, and nuts
  • fruit

Predation

Predation on D. matschiei is poorly known. They are hunted by humans and perhaps large birds of prey. These tree kangaroos avoid predation largely by seeking refuge in trees.

Ecosystem Roles

This tree kangaroo's consumption of mature leaves has little effect on the canopy given the current population size. The occasional consumption of young domestic birds is not frequent enough to have any ecosystem impact.

Economic Importance for Humans: Positive

Internationally, this species of tree kangaroo is valued in zoos as a brilliantly colored unusual kangaroo. Locally, it is hunted as a food source. (Procter-Gray 1990)

Economic Importance for Humans: Negative

There are no adverse affects of D. matschiei on humans.

Conservation Status

In 1996, the IUCN listed D. matschiei as seriously endangered, meaning 50% of the population has disappeared in the past ten years. Rainforest clearing and hunting are the main threats. Dendrolagus matschiei is the focus of a Species Survival Plan organized by international zoos. This plan focuses on habitat preservation and field studies while at the same time maintaining and studying the large captive population to learn more about tree kangaroo biology. Education is also stressed in an attempt to reduce the joint pressures of rainforest destruction and hunting.

(Collins 1990, IUCN 1996, http://www.aza.org/aza/ssp/trekang.html)

Other Comments

Dendrolagus comes from the Greek word dendron, meaning tree, and lagos, meaning hare. Dendrolagus matschiei was named after the German zoologist Paul Matschie, who discovered several other species of tree kangaroo. In captivity, tree kangaroos are particularly susceptible to atypical strains of mycobacteria, resulting in tubercular lesions. In a 1990 survey of institutions holding tree kangaroos, 8% of necropsies involved mycobacterial infections (excluding newborns). For Matschie's tree kangaroos, 73 % of reported mycobacterial infections were traced to an avian strain of tuberculosis. Routes of infection are assumed to be similar to those in humans: inhalation of infectious aerosols or inoculation from wounds or lacerations, yet animals housed together with infected individuals do not become infected. As in humans, most infections are believed to be acquired from the environment, not other individuals.

In the past, tree kangaroos infected with mycobacteria were often euthanized without any treatment attempt. Given the endangered status of these animals and the availability of antitubercular drugs, early diagnosis and treatment is important. Although few cases of tuberculosis in tree kangaroos have been directly linked to birds housed in the same area, the Species Survival Plan now recommends that no birds be housed with tree kangaroos. Stress on these animals also needs to be minimized since stress is associated with immunosuppression, which is always found in latently infected individuals. Early screening with skin tests, chest radiographs and cultures are also being routinely practiced. Further culture and isolation of mycobacteria from infected individuals will shed more light on the origin of infection.

(Flannery 1990, Collins 1990, Joslin 1990)

Glossary

Australian

Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.

World Map

acoustic

uses sound to communicate

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

arboreal

Referring to an animal that lives in trees; tree-climbing.

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

diurnal
  1. active during the day, 2. lasting for one day.
ecotourism

humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.

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.

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.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

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.

polygynandrous

the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

rainforest

rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

sedentary

remains in the same area

sexual

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

solitary

lives alone

tactile

uses touch to communicate

terrestrial

Living on the ground.

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

year-round breeding

breeding takes place throughout the year

References

Collins, Larry (International Studbook Keeper for Matschie's Tree Kangaroo). 1990. Tree Kangaroo Husbandry Notebook. Tree Kangaroo Species Survival Plan. National Zoological Park Conservation and Research Center, Front Royal, Virginia.

Flannery, Tim. 1995. Mammals of New Guinea. Reed Books, Chatswood, NSW.

Groves, C.P. 1982. "The Systematics of Tree Kangaroos." Australian Mammalogy. 5(3): 187-196.

http://www.aza.org/aza/ssp/trekang.html

International Union for the Conservation of Nature and Natural Resources. 1996. 1996 IUCN Red List of Threatened Animals. IUCN, Gland, Switzerland.

Joslin, Janis Ott. 1990. "Mycobacterial Infections in Tree Kangaroos." 1990 Proceedings of the American Association of Zoo Veterinarians.

Moeller, Heinz F. 1990. "Tree Kangaroos" Grzimek's Encyclopedia of Mammals. Volume I. McGraw Hill Publishing Company, New York.

Procter-Gray, Elizabeth. 1990. "Kangaroos up a Tree." Natural History. 1/90.

Wilson, Don E. and Dee Ann Reeder, editors. 1993. Mammal Species of the World. Second Edition. Smithsonian Institue Press, Washington, DC.