Osphranter rufus (Desmarest, 1822)

Russell A. Mittermeier & Don E. Wilson, 2015, Macropodidae, Handbook of the Mammals of the World – Volume 5 Monotremes and Marsupials, Barcelona: Lynx Edicions, pp. 630-735 : 726-727

49.

Red Kangaroo

Osphranter rufus

French: Kangourou roux / German: Rotes Riesenkanguru / Spanish: Canguro rojo

Other common names: Blue Flier, Plains Kangaroo

Taxonomy. Kangurus rufa Desmarest, 1822 ,

“ L’intérieur de la Nouvelle-Hollande audela des Montagnes-Bleues [= beyond the Blue Mountains],” New South Wales, 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. Inland and W Australia.

Descriptive notes. Head-body 93.5-140 cm (males) and 745-110 cm (females), tail 71-100 cm (males) and 64.5-90 cm (females); weight 22-92 kg (males) and 17-39 kg (females). The largest living marsupial. A large, lean, but muscular, highly sexually dimorphic kangaroo, with short square snout, black-and-white markings on face, and long pointed ears. The fur is dense and short. Males typically brick-red and females blue-gray dorsally, both sexes off-white to cream ventrally and on lower limbs and tail, but blue-gray males, red females, and intermediate individuals also occur. Head blue-gray, black-and-white markings on side of muzzle, broad pale cheek stripe from corner of mouth to base of ear; paws and digits of feet dark brown to black. Pinkish staining often present on chest and neck of adult males. Body size increases with latitude (Bergmann’s rule). Diploid chromosome number is 20.

Habitat. Open plains of semi-arid and arid zone, where mean annual temperature is high and annual rainfall generally low and erratic. Occurs in low chenopod shrubland, mulga, and brigalow shrubland, sandplain grassland, hummock grassland, and floodout plains at base of rocky outcrops and ranges, in proximity to permanent water. Almost never in hilly areas. Favors more moist and fertile soils dominated by forbs and short grasses rather than taller, perennial grasses. Reaches highest density in semi-arid rangelands of New South Wales and Queensland. Avoids areas of concentrated grazing by sheep, but shows no spatial interaction with cattle. Requires patches of trees or shrubs for shade.

Food and Feeding. Predominantly a grazer, but dicotyledonous forbs often also comprise a large proportion (38-99%) of diet. Consumes green leaves, stems, and seeds of grasses, and leaves and fruit of woody dicotyledons. A highly selective feeder, preferring grass, forbs, and malvaceous and solanaceous subshrubs, and avoiding chenopod shrubs (saltbushes and bluebushes) and trees. Under dry conditions, when availability of grasses and forbs declines to very low levels, the intake of bluebush, saltbush, and shrubs such as Acacia and Cassia (both Fabaceae ), or Eremophila (Scrophulariaceae) increases. During drought, females appear able to consume a higher proportion of forbs and grass than do males.

Breeding. Females reach sexual maturity from 15 months and males from 24 months. Breeds continuously in good conditions, females producing one young per pregnancy, although twins are occasionally reported. Exhibits embryonic diapause and post-partum estrus, females mating within a few days of giving birth. Females may, however, enter anestrus during prolonged drought, and does not therefore undergo post-partum estrus or return to estrus when the pouch young dies. Rapidly return to estrus in response to rainfall. The estrous cycle averages 34-35 days and gestation 32-34 (mean 33) days. Young spend 7-5-8 months in the pouch and are weaned at about twelve months. After permanent pouch emergence, young accompany their mother as a young-at-foot until after weaning. There is intense competition among males for access to females. Males establish dominance relationships through repetitive, ritualized bouts of grooming, display, sparring, wrestling, and kicking. They routinely test the estrous state of females by eliciting urination, nosing the stream, and exhibiting flehmen (lip-curl). The dominant male guards an estrous female, defending her from up to ten (sometimes more) rival males. Copulation is relatively brief, occurring over 10-25 minutes, sometimes in multiple short bouts.

Activity patterns. Crepuscular to nocturnal. Foraging activity is bimodal, with a peak 3-5 hours after sunset and a second about an hour before and after sunrise. Activity is reduced around midnight, but only slightly in hot weather, and is higher during day in cold, wet weather. Restless in daytime during hot weather, alternately moving in and out of shade, digging hip-holes, lying and standing crouched, and licking forelimbs for evaporative cooling in shade of trees and shrubs. Visits water sources in hot weather; visits are brief (average 9-12 minutes) and peak at dusk, but continue through night, and sometimes occur in hottest part of day.

Movements, Home range and Social organization. Sedentary to mobile. Home ranges of both sexes overlap extensively, but are generally larger for males. Average sizes of home ranges (95% Fourier transform, MAP95) at three semi-arid sites were 463 ha (both sexes), 444 ha for females and 638 ha for males, and 472 ha for females and 1879 ha for males. Average home ranges (95% Fourier transform, MAP95) in arid areas are considerably larger: 1840 ha for males and 3680 ha for females. Home ranges typically encompass water points, but some individuals make brief excursions beyond their normal range to visit water. In prolonged dry conditions, individuals may vacate their home range and move 25-30 km to exploit patches of new growth after thunderstorms, resulting in localized concentrations of individuals, often returning to their home ranges later. Individuals translocated to sites 13-20 km away returned to their home ranges. Occasional, spontaneous long-distance movements (more than 300 km), not stimulated by rain events or restricted to any sex or age class, have also been recorded. Natal dispersal is male-biased and has been reported over distances exceeding 30 km. Genetic studies indicate that extensive female gene flow can occur over up to 1000 km. Gregarious; forms open-membership groups, which frequently change in size and composition and can hold as many as 25 individuals. Average group size is 2-3; group size is positively related to population density. Individuals in larger groups spend less time scanning for predators and more time feeding in open habitat, and to lesser extent in shrubby habitat. Mixed-sex groups occur throughout the year when breeding asynchronous, but once rainfall has synchronized breeding they are more common when most females are carrying large pouch young. Large adult males are also often seen alone as they rove across their home ranges, checking reproductive status of adult females.

Status and Conservation. Classified as Least Concern on The IUCN Red List. The Red Kangaroo is widespread and locally common through much ofits range. It is well represented in protected areas and is not currently facing any major threats. Some of its habitat has been lost to urbanization and intensive agriculture. In other areas, however, Red Kangaroos have benefited from the clearing of forest/woodland, the establishment of pasture, and the provision of water for livestock, as well as the suppression of predators. These changes have enabled the species to expand its distribution and increase in local density in some areas. At some sitesit is regarded as an agricultural pest and periodic culling is undertaken. Red Kangaroos are also commercially harvested in New South Wales, Queensland, South Australia, and Western Australia. They are also subject to local hunting by Aboriginal people in central Australia. Research is required into this macropodid’s population genetics and population dynamics, including potential impacts of climate change on behavior, survival, and mobility.

Bibliography. Andrew & Lange (1986), Bailey (1971), Bailey et al. (1971), Barker (1987), Calaby & Grigg (1989), Caughley (1964a, 1964b), Caughley, Short et al. (1987), Chippendale (1968), Clegg et al. (1998), Coulson & Croft (1981), Croft (1981a, 1991a), Croft & Clancy (2008), Croft & Snaith (1991), Dawson & Flannery (1985), Dawson, McTavish & Ellis (2004), Dawson, McTavish, Munn & Holloway (2006), DOE (2012), Dudzinski et al. (1982), Eldridge & Rath (2002), Ellis, van Weenen, Copley et al. (2008), Frith (1964), Frith & Sharman (1964), Griffiths & Barker (1966), Griffiths et al. (1974), Groves (2005b), Harris, D.B. et al. (2014), Hayman (1989), Jackson & Groves (2015), Johnson, C.N. (1983), Johnson, C.N. & Bayliss (1981), Johnson, PM. (2003), Letnic & Crowther (2013), Low (1979), Low, Birk et al. (1973), Low, Muller et al. (1981), MacFarlane & Coulson (2005), McAlpine et al. (1999), McCullough & Mc-Cullough (2000), Menkhorst & Knight (2001), Montague-Drake & Croft (2004), Newsome (1965, 1975), Norbury & Norbury (1993), Norbury et al. (1994), van Oorschot & Cooper (1989), Pople, Grigg et al. (2010), Pople, Phinn et al. (2007), Priddel (1986, 1987), Priddel, Shepherd & Ellis (1988), Priddel, Shepherd & Wellard (1988), Priddel, Wellard & Shepherd (1988), Russell (1970, 1971), Russell & Harrop (1976), Russell & Nicholls (1972), Sharman & Calaby (1964), Short et al. (1983), Underhill et al. (2007), Watson & Dawson (1993), Wilson (1991), Yom-Tov & Nix (1986).

Figures

47. Eastern Grey Kangaroo (Macropus giganteus), 48. Western Grey Kangaroo (Macropus fuliginosus), 49. Red Kangaroo (Osphranter rufus), 50. Black Wallaroo (Osphranter bernardus), 51. Antilopine Wallaroo (Osphranter antilopinus), 52. Common Wallaroo (Osphranter robustus), 53. Whip-tailed Wallaby (Notamacropus parryi), 54. Agile Wallaby (Notamacropus agilis), 55. Red-necked Wallaby (Notamacropus rufogriseus), 56. Western Brush Wallaby (Notamacropus irma), 57. Black-striped Wallaby (Notamacropus dorsalis), 58. Tammar Wallaby (Notamacropus eugenii), 59. Parma Wallaby (Notamacropus parma)

Distribution. Inland and W Australia.