Petrogale concinna

Geographic Range

Petrogale concinna is found in two, disjunct areas of Australia: the Northern Territory of Australia, including the neighboring islands of Borda, Augustus, Long, and Hidden, and northwestern Kimberly area in western Australia. These populations have generally been considered subspecies: Petrogale concinna canescens and Petrogale concinna monastria .

• Biogeographic Regions
• australian australian
  • native native

Habitat

Petrogale concinna is restricted to the sandstone or granite rocky hills, cliffs and gorges of northern Australia.

• Habitat Regions
• tropical tropical

• Terrestrial Biomes
• savanna or grassland savanna or grassland

Physical Description

Petrogale concinna has dull, reddish colored fur with light grey and black marbling. The belly is greyish-white. The tip of tail is black and bushy. The fur is short with a soft, silky texture. The soles of the feet are thickly padded and granulated in order to grip rock; these animals use skin friction rather than large claws to climb. Body size varies among individuals. Head and body length can range from 310-365 mm; the tail can range 260-335mm; hind feet can be 95-105 mm; ear length can be 41-45 mm; and weight can range from 1200-1600g g.

The teeth of Petrogale concinna are unique among marsupials. Throughout life, the molars of P. concinna continually erupt. The old molars are pushed forward until they eventually fall out in the front of the mouth. The actual number of molars is unknown. As many as nine molars can successively erupt, but there are seldom more than five molars in place at any time. Researchers believe this phenomenon could be an adaptation to the ferns that they eat, because fern tissue is extremely abrasive.

As Petrogale concinna runs, it carries its body horizontally with its tail arched high over its back.

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes alike

Reproduction

Little is known about this species in the wild. Captive Petrogale concinna females are known to attack males after mating by kicking and bites to the back of head and neck. If the male was not removed, he would be killed.

Captive Petrogale concinna breed throughout the year, and post-partum estrus and embryonic diapause occur. The estrous cycle lasts from an average of 31-36 days. Dominant females posess a shorter estrous cycle than subordinant females. Females have one offspring per litter and gestation lasts roughly thirty days. The time to weaning in P. concinna is much shorter than that of the other species in its genus. After 160 days outside of the pouch, the joey is completely weaned and, in 175 days, it is independent.

• Key Reproductive Features
• iteroparous iteroparous
• year-round breeding year-round breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• viviparous viviparous
• embryonic diapause embryonic diapause
• post-partum estrous

Females nurse and care for their young until they reach independence. Once the young are weaned, mothers do not tolerate their continued presence. Females drive off young when they attempts to suckle. They may bite at the tail of the young, occasionally causing the tail to become lost due to irritation caused by bites.

• Parental Investment
• altricial altricial
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female
  • protecting
    • female

Lifespan/Longevity

The maximum known lifespan of Petrogale concinna is 17 years.

Behavior

Petrogale concinna is mostly nocturnal and timid. Members of this species occasionally like to bask in the morning. They are also gregarious, living in groups.

• Key Behaviors
• terricolous
• saltatorial saltatorial
• nocturnal nocturnal
• motile motile
• sedentary sedentary
• territorial territorial

Home Range

The home range is not known, however a territory is occassionally shared with Petrogale brachyotis (a rock wallaby similar to Petrogale concinna ).

Communication and Perception

Marsupials are rarely vocal. When they are used, vocalizations play a role primarily in mating, territorial, and mother to young encounters. Captive Petrogale concinna displayed vocalization during adult female encounters. Using vocalization establishes dominance among females. Vocalization was nearly always given by the defending animal, with each call appearing to have different functional significances. Threat calls are screams, given in response to an attack; sneezes are given at intermediate distances in response to movements of the opponent; coughs are threat calls given in response to an approach; barks are hesitant calls that are generally given at long distances.

• Communication Channels
• tactile tactile
• acoustic acoustic

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

Petrogale concinna does not stray far from the safety of its rock shelter, except that at night it may travel far distances to feed on grasses, sedges and ferns. During the dry season this species relies on a fern Marsilea crenata , feeding primarily on grasses during the wet season.

Unlike most macropodids , adult P. concinna lack a specialized structure called a gastric sulcus. This structure is found in most herbivores that have modified stomachs for microbial fermentation of food, and facilitates movement of liquid digesta. Captive P. concinna were seen frequently regurgitating food. According to Goldstone and Nelson “this behavior is not analogous to rumination in ruminants and has been termed mercyism”.

• Primary Diet
• herbivore herbivore
  • folivore folivore

• Plant Foods
• leaves
• roots and tubers

Predation

Current threats to P. concinna include habitat change by altered fire regimes and possible attacks by feral cats.

Ecosystem Roles

Members of this species are herbivores. They may play a role in determining the structure of plant communities.

• Ecosystem Impact
• disperses seeds

Economic Importance for Humans: Positive

Little is known about Petrogale concinna .

• Positive Impacts
• research and education

Economic Importance for Humans: Negative

No known negative economic importance.

Conservation Status

Although Petrogale concinna is not listed as being threatened it is found on two of Australia's conservation reserves; Kakadu and Litchfield National Parks.

Other Comments

There are fifteen known species of rock wallabies including P. concinna . Petrogale concinna has a variety of names such as the Nabarlek and little pigmy rock wallaby. It was discovered in 1842 by a gentleman by the name of Gould.

Additional Links

Encyclopedia of Life

Contributors

Tanya Dewey (editor), Animal Diversity Web.

Cassandra Dunham (author), University of Michigan-Ann Arbor, Phil Myers (editor, instructor), Museum of Zoology, University of Michigan-Ann Arbor.

References

Aitkin, L. 1998. Hearing- The Brain and Auditory Communication in Marsupials . New York: Springer.

Churchill, 1997. Habitat use, distribution and conservation status of the Nabarlek Petrogale concinna, and sympatric rock-dwelling mammals in the Northern Territory. Australian Mammalogy , 19: 297-308.

Goldstone, A., J. Nelson. 1986. Aggressive Behaviour in Two Female Peradorcas concinna (Macropodidae) and its relation to Ostrus. Australian Wildlife Res. , 13: 375-85.

Hume, I. 1999. Marsupial Nutrition . United Kingdom: Cambridge University Press.

Maxwell, S., A. Burbidge, K. Morris. 1996. "Action Plan for Australian Marsupials and Monotremes" (On-line). Australian Government; Department of the Environment and Heritage. Accessed April 18, 2006 at http://www.deh.gov.au/biodiversity/threatened/action/marsupials/27.html .

Menkhorst, P., F. Knight. 2004. A Field Guide to the Mammals of Australia . Melbourne: Oxford University Press.

Nelson, J., A. Goldstone. 1986. Reproduction in Peradorcas concinna Marsupialia: Macropodidae. Austrailian Wildlife Research , 13: 501-505.

Nowak, R. 1991. Walker's Mammals of the World . Baltimore & London: The John Hopkins University Press.

Taylor, M. 1984. Mammals of Australia . Melbourne: Oxford University Press.

Woinarski, J., A. Burbidge, W. Telfer, N. McKenzie, T. Start. 2008. "Petrogale concinna" (On-line).

IUCN Red List of Threatened Species. Version 2013.2

Commonwealth of Australia. 2004. "Elevations" (On-line). Australian Government. Accessed April 17, 2006 at http://www.ga.gov.au/education/facts/landforms/elevatio.htm#Elevation%20Map .

Ohio University. 2006. "Sheet 1" (On-line). Accessed April 17, 2006 at http://oak.cats.ohiou.edu/~milesd/marsupial_lh.xls .