Geographic Range
Papuan forest wallabies,
Dorcopsulus maclaeyi
, are endemic to southern New Guinea. This species is restricted to the rain forest
near Port Moresby on the south coast of south-eastern Papua New Guinea.
- Biogeographic Regions
- oceanic islands
- Other Geographic Terms
- island endemic
Habitat
Papuan forest wallabies utilize cover and roaming space within the dense forests of
New Guinea. They prefer dry areas that are heavily covered by tall trees and have
rich floor vegetation. However, expansion of the broad plains containing savannah
woodland and grasslands (maintained largely by periodic native burning) has pushed
Papuan wallabies to move to higher elevations (1200 to 1300 m) in the forest.
- Habitat Regions
- tropical
- terrestrial
- Terrestrial Biomes
- forest
- rainforest
Physical Description
Dorcopsulus macleayi is the smallest marsupial in its genus. Pelage is a general brownish-grey and it is lighter ventrally. The tip of the tail is nearly bare and is white in color.
The skull is smaller, shorter, and broader in comparison to the other members of its
genus. Head and body measure 490 mm. The tail averages 320 mm, and the hind foot
is 115 mm. Individuals weigh between 3 and 5 kg.
The dentition of
D. macleayi
is characterized by a pair of incisors that are small, light, and that do not touch
each other. The canines are short and slender, whereas the molars are broad, evenly
oval, and shorter than other
Dorcopsulus
.
- Other Physical Features
- endothermic
- bilateral symmetry
- Sexual Dimorphism
- sexes alike
Reproduction
Both male and female Papuan forest wallabies grow to about the same size and mature
sexually about the same time. Mating is typically polygynandrous. Males commit fewer
resources than females to the production of each offspring. Males engage in little
pre-mating behavior and increase their chances of producing offspring by mating with
as many females as possible.
- Mating System
- polygynandrous (promiscuous)
Breeding of Papuan forest wallabies occurs mostly in late January and early February.
Reproduction is apparently related to female physiological condition. Because females
invest so much energy in reproduction, a female will only enter estrus if she has
enough energy and resources to successfully rear her offspring.
As is true of all marsupials, the young are born after a short gestation. At birth,
young are altricial. They complete their development inside their mother's pouch.
Gestation is reported to last 21 days. Weaning probably occurs when the young leave
the pouch at about 18 months of age. Of two records of females with offspring, one
female had two young in the pouch, another had only one pouch young. Based on this,
it is likely that only one or possibly two offpsring are produced at a time. Reproductive
maturity is reached around the age of 2 years.
- Key Reproductive Features
- iteroparous
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- fertilization
- viviparous
The gestation period is about 21 days. Birth is so rapid that females do not even
feel when their young are born. The newborn moves from the vagina into the pouch and
attaches itself to a teat. After birth, a young wallaby may spend up to 18 months
inside the pouch.
The energy needed for daily activity remains low for many marsupial mothers during
gestation. This indicates that the growing fetus requires little energetic investment
from the mother. Investment in the young after birth is substantial, however. A female
lactates for the entire time the young is in her pouch. Males do not stay around to
look after the young, leaving the rearing of offspring to the mother.
- Parental Investment
- altricial
-
pre-fertilization
- provisioning
-
protecting
- female
-
pre-hatching/birth
-
provisioning
- female
-
protecting
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- female
-
protecting
- female
-
provisioning
- extended period of juvenile learning
Lifespan/Longevity
There are no records of the lifespan of
D. macleayi
. However, a related species found in the same geographic range but at lower altitudes,
Dorcopsulus luctuosa
, has a maximum lifespan of eight years.
Dorcopsulus macleayi
probably has similar longevity.
Behavior
Papuan forest wallabies are terrestrial herbivores/browsers. They forage on the soil
surface for the most part and have limited ability to burrow. Their ability to survive
on open habitat is reduced because they are forest specialists. They are presumed
to be nocturnal.
Home Range
Communication and Perception
Like most marsupials, Papuan forest wallabies have a well-developed sense of smell. Females release a strong scent when they are in estrus and ready to find a mate. In addition to using this olfactory cue of mating readiness, males also smell the genital area of a female to make sure that no young are already in the pouch.
In addition to olfactory communication, it is likely that in mating and during the
pouch life of an offspring, much tactile information is exchanged. Visual cues may
also be used in communication, but have not been documented. Similarly, the role
of vocal communication has not been investigated.
- Other Communication Modes
- scent marks
Food Habits
Dorcopsulus macleayi
is a generalist browsing herbivore. Its diet is composed of leaves, buds, and stems
of dictotyledonous plants.
- Plant Foods
- leaves
- wood, bark, or stems
Predation
The major predators of this species are
New Guinea harpy-eagles
,
carpet pythons
, and
wedge-tailed eagles
.
Ecosystem Roles
These wallabies are an important part of their ecosystem. They serve as prey for many
animals, and have some affect on the vegetation they feed upon.
Economic Importance for Humans: Positive
Several native tribes of the Papuan forest regions have used the furs of Papuan wallabies
as a means of trade and as bridal gifts. Beyond this limited use, the species holds
no real economic importance for humans.
- Positive Impacts
- body parts are source of valuable material
Economic Importance for Humans: Negative
There is no known negative impact of this species on humans.
Conservation Status
Currently, D. macleayi is considered a vulnerable species that is subject to the effects of human activities. It has an unpredictable future. IUCN says that this species can very easily become critically endangered.
Several organizations are now working with farmers in New Guinea to protect and preserve the forests and the land, and are also helping preserve wildlife. They may be assisting the survival of this wallaby species.
In 1994, the World Wildlife organization began the Kikori Integrated Conservation and Development Project to promote wildlife management along with managed forestry and community development ideas. This project significantly helps conserve the endemic species of the forest.
Conservation Melanesia is another project works in Pacific Islands to protect the
habitat for the species that dwell in the forest.
Additional Links
Contributors
Daniel Rosas Alvarez (author), University of Notre Dame, Karen Powers (editor, instructor), Radford University.
Nancy Shefferly (editor), Animal Diversity Web.
- oceanic islands
-
islands that are not part of continental shelf areas, they are not, and have never been, connected to a continental land mass, most typically these are volcanic islands.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- island endemic
-
animals that live only on an island or set of islands.
- tropical
-
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
- terrestrial
-
Living on the ground.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- 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.
- polygynandrous
-
the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.
- 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).
- seasonal breeding
-
breeding is confined to a particular season
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- fertilization
-
union of egg and spermatozoan
- viviparous
-
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
- 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.
- nocturnal
-
active during the night
- motile
-
having the capacity to move from one place to another.
- sedentary
-
remains in the same area
- social
-
associates with others of its species; forms social groups.
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- scent marks
-
communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- herbivore
-
An animal that eats mainly plants or parts of plants.
- folivore
-
an animal that mainly eats leaves.
- 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.
- 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.
References
Australian Marsupial and Monotreme Specialist Group, 2004. " Dorscopsulus macleayi " (On-line). Accessed April 09, 2006 at http://www.iucnredlist.org/ .
Cockburn, A., A. Lee. 1985. Evolutionary Ecology of Marsupials . New York: Cambridge Press.
Dutson, G. 2004. "Papua New Guinea Tour Report" (On-line pdf). Accessed April 09, 2006 at http://birdquest.co.uk/reportfiles/papua%20new%20guinea%20rep%2004.pdf .
Fisher, D., I. Owens, C. Johnson. 2001. "The ecological basis of life history variation in marsupials" (On-line). Ecological Archives. Accessed April 09, 2006 at http://esapubs.org/archive/ecol/E082/042/appendix-A.htm .
Gilmore, D., B. Stonehouse. 1977. The Biology of Marsupials . London: University Park Press.
Lydekker, R. 1896. A Handbook to the Marsupalia and Monotremata . London: Edward Lloyd.
Nowak, R. 1999. Walker's Mammals of the World, Sixth Edition . Baltimore and London: The Johns Hopkins University Press.
Oldfield, T. 1888. Catalogue of the Marsupialia and Monotremata in the collection of the British Museum . London: Taylor and Francis.
Renfree, M., H. Tyndale-Biscoe. 1987. Reproductive Physiology of Marsupials . New York: Cambridge Press.
Tomasek, A. 2001. "About New Guinea" (On-line). WorldWildLife.org. Accessed April 10, 2006 at http://worldwildlife.org/expeditions/newguinea/about.cfm .