Osphranter bernardus

50.

Black Wallaroo

Osphranter bernardus

French: Wallarou noir / German: Schwarzes Bergkanguru / Spanish: \ Walaré negro

Other common names: Bernard's Kangaroo, Bernard's Wallaroo, Black Kangaroo, Northern Black Wallaroo

Taxonomy. Macropus bernardus Rothschild, 1904,

“ Head of South Alligator River,” Northern Territory, Australia.

Previously placed in genus Macropus, within which moved into subgenus Osphranter in 1985; in 2015 Osphranter was elevated to full genus status. Monotypic.

Distribution. N Australia, confined to W Arnhem Land E of South Alligator River, Northern Territory.

Descriptive notes. Head-body 59-5— 72-5 cm (males) and 64-6 cm (one female), tail 54-5—64 cm (males) and 57-5 cm (one female); weight 19-22 kg (males) and 13 kg (one female). A small, stocky, sexually dimorphic wallaroo, with shaggy fur and relatively short oval ears. Male black to dark brown, sometimes lighter brown or yellowish on face, arms and chest; feet, paws, and tail black. Female light gray to gray-brown, paler ventrally, darker on crown; paws,feet, and tail tip dark brown to black. Diploid chromosome number is 18.

Habitat. Deeply dissected sandstone plateaus and steep rocky escarpments supporting monsoon rainforest, tropical eucalypt woodland, hummock grassland, and heath. Favors areas with large boulders.

Food and Feeding. Consumes grasses, as well as browse, forbs, fruits, seeds, and flowers from a variety of plants. Consumes more grass in wet season and more browse, including rock-specialist plants, in dry season. Also selects grasses resprouting afterfire.

Breeding. Poorly known. Likely to produce a single young. Large pouch young regularly present June to September. Adult males are significantly larger than adult females, suggesting intense competition among males for access to females.

Activity patterns. Poorly known. Primarily nocturnal, but may be active on overcast days during wet season. Typically spends daylight hours in a cave, under rock overhang, or in shade of dense vegetation, moving into surrounding area at night to feed. Sheltersites reported to be regularly used by same individual. May descend to base of escarpment to forage or drink from rock pools.

Movements, Home range and Social organization. Poorly known. Agile in complex rocky habitat, less nimble on flat terrain. Shy and wary, rapidly flees to safety of escarpment when disturbed. Usually solitary, but pairs occasionally observed.

Status and Conservation. Classified as Near Threatened on The IUCN Red List. The specialized habitat and highly restricted distribution of the Black Wallaroo make it inherently vulnerable to extinction. The difficulty in accessing its habitat, combined with the species’ elusive nature, makes accurate assessment of its conservation status problematic. Aerial surveys in 1980s indicated that the Black Wallaroo was locally common, but more recent discussions with Aboriginal people suggest that it may be declining. Although most ofits distribution is contained within protected areas, the long-term impact of altered fire regimes and ongoing low-level indigenous hunting should be monitored. Black Wallaroos have been occasionally maintained in captivity in Australia, but a viable captive population has not been established. Research into all aspects of this macropodid’s biology is urgently required.

Bibliography. Dawson & Flannery (1985), Groves (2005b), Jackson & Groves (2015), Menkhorst, K.A. & Wolinarski (1992), Menkhorst, PW. & Knight (2001), Parker (1971), Press (1988, 1989), Sharman (1989), Telfer & Bowman (2006), Telfer & Calaby (2008), Telfer & Garde (2006), Telfer et al. (2008), Woinarski (2008d), Woinarski et al. (2014aa), Ziembicki et al. (2013).