Petrogale lateralis, Gould, 1842

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 : 712-713

33.

Black-footed Rock Wallaby

Petrogale lateralis

French: Wallaby a pattes noires / German: Schwarzpfoten-Felskanguru / Spanish: Ualabi rupestre de pies negros

Other common names: Black-flanked Rock Wallaby, Black-flanked Rock-wallaby, Black-footed Rock-wallaby, Side-striped Rock Wallaby; Hackett's Rock Wallaby/Recherche Rock Wallaby (hacketti), Pearson Island Rock Wallaby (pearsoni), Warru (MacDonnell Ranges form), West Australian Rock Wallaby / West Kimberley Rock-wallaby (West Kimberley form)

Taxonomy. Petrogale lateralis Gould, 1842 ,

“ Swan River ,” south-west Western Austral-1a, Australia.

A memberof the lateralis / penicillata group of species (which includes also P. rothschildi, P. purpureicollis , P. penicillata , P. herberti , P. inornata , P. assimilis , P sharmani , P mareeba , P. godmani , P. coenensis ). Formerly regarded as a subspecies of P. penicillata , but reinstated as a full species in 1982. Populations in West Kimberley (Western Australia) and MacDonnell Ranges (central Australia) represent two additional subspecies, yet to be formally described; they are currently known as the MacDonnell Ranges and West Kimberley races, respectively. Three subspecies recognized.

Subspecies and Distribution.

P.l.lateralisGould,1842—patchilyacrossSWesternAustralia,includingCapeRange,LittleSandyDesert,andthenearKellerberrininWheatbelt;alsoBarrowIandSalisburyI.

P.l.hackettiThomas,1905—islandsofWilson,Mondrain,andWestall(RechercheArchipelago),WesternAustralia.Mayhaveoccurredhistoricallyalsoonadjacentmainland.

P. l. pearson: Thomas, 1922 — North Pearson I, Investigator Group, South Australia. Introduced to South and Middle Pearson, Thistle, and Wedge Is, South Australia.

A hitherto undescribed subspecies, the West Kimberley race, occurs (distributional limits uncertain) in Edgar, Grant, and Erskine Ranges and on Mt Wynne, Mt Anderson, and Mt Alexander, in S West Kimberley, Western Australia. A second undescribed subspecies, the MacDonnell Ranges race, is present in MacDonnell Ranges of C Australia, extending to E Western Australia and N South Australia.

Descriptive notes. Head-body 45.2-52.9 cm (males) and 44.6-48.6 cm (females), tail 48.3-60.5 cm (males) and 40.7-51.6 cm (females); weight 3.3-5 kg (males) and 2.9-3.8 kg (females) for P. [ l. lateralis ; head-body 50-57 cm, tail 46-57.4 cm; weight 4.8-5.3 kg for P. I. hacketti; head-body 56.5-57 cm (males) and 48-3 cm (female), tail 32:3-51 cm (males) and 34.5-42 cm (females); weight 3-5—4-6 kg (males) and 2-3— 3-4 kg (females) for P. I. pearsoni; head—body 47-5 cm (male), tail 48.7-53 cm (males) and 45-48.5 cm (females); weight 3.5-6.5 kg (males) and 3.3-4.2 kg (females) for undescribed West Kimberley race; head—body 49.5-52.1 cm (males) and 44.9-47 cm (females), tail 49-61.3 cm (males) and 44.5-59 cm (females); weight 4.1-5.2 kg (males) and 2.8-4.4 kg (females) for undescribed MacDonnell Ranges race. P. [. lateralis is dark gray-brown, paler on chest and passing to dark brown on belly. Face dark with distinct pale cheek stripe, light brown patches at base of ears; dark brown to black dorsal stripe from between ears to beyond shoulders; feet pale brown, digits black; arms pale dorsally, darker ventrally, paws dark brown to black; white side stripe with wider dark brown stripe immediately ventral, extending from dark axillary patch to thighs; tail brownish gray, becoming black distally, with slight terminal brush. Fur thick and woolly, particularly about rump, flanks, and base oftail. Pelage is lighter and browner in summer. Diploid chromosome number is 22. P. I. hackettiis similar to P. L. lateralis but larger. Diploid chromosome number is 20. “Pearson Island Rock Wallaby” is grizzled gray-brown dorsally, shoulders and neck silvery, chest and belly pale yellow to buff; face dark gray-brown with wide pale cheek stripe, also pale chin, below eyes, and base of ears; distinct dark dorsal stripe from between ears to beyond shoulders; arms white, becoming buff distally, paws dark brown to black; white side stripe with wider dark brown stripe immediately ventral, extending from dark axillary patch to thighs; tail short, light brown, becoming black distally, with slight terminal brush. Fur thick and woolly. Diploid chromosome number is 22. West Kimberley race has similar markings to those of P. I. lateralis , but coloration paler and distinctly yellowish. Diploid chromosome number is 20. MacDonnell Ranges race is similar to P. I. lateralis , but more gracile, with longertail, less prominent tail brush, shorter, less dense fur, and more gray in coloration; dark grizzled brown dorsally, gray on shoulders, paler ventrally; pale cheek stripe; ears dark brown, paler smoky brown at base; dark brown to black dorsalstripe from between ears to beyond shoulders; feet gray-brown, digits black; arms sandy dorsally and darker ventrally, paws dark brown to black; white side stripe with wider dark brown stripe immediately ventral, extending from dark axillary patch to thighs; tail dark gray, becoming browner distally, with slight terminal brush. Pelage changes to sandy brown in summer. Diploid chromosome numberis 22.

Habitat. Rocky outcrops, boulder piles, rocky slopes, cliffs, and gorges in a wide range of woodland, shrubland, and grassland habitats ranging from temperate to tropical and from mesic to arid.

Food and Feeding. Consumes a variety of grasses, forbs, and browse. Seeds and fruit are also occasionally eaten. Does not require access to free water.

Breeding. Breeds throughout year, although there is an autumn—winter peak in births in southern populations. Breeding also may be reduced in drought periods. Exhibits embryonic diapause and post-partum estrus, females mating shortly after giving birth. The estrous cycle and gestation are both ¢.30 days. A single young is born and spends 6-6-5 months in the pouch.

Activity patterns. Largely nocturnal in summer, crepuscular or partially diurnal in other months. On cold mornings sits on exposed rocks to bask in the sun for several hours before moving to den sites. Shelters during day among rocks or within boulder piles. Moves off rocks in late afternoon or early evening to feed.

Movements, Home range and Social organization. Tends to feed close to its rocky shelters, but may venture up to 300 m into open areas to feed. Home range of one adult female of MacDonnell Ranges race was 171 ha (90% minimum convex polygon) in winter. Although individuals typically show high fidelity to their resting sites, they can travel several kilometers in a single night. Colonies of more than 100 individuals may occupy some habitat patches, although individuals often rest and forage alone. In captivity, both males and females can be highly aggressive toward members of same sex. Genetic data suggest that dispersal is limited, populations 500 m to 1 km apart showing genetic differentiation. Successful dispersal between outcrops up to 8 km apart has, however, been recorded.

Status and Conservation. Classified as Near Threatened on The IUCN Red List. Subspecies lateralis and hacketti, as well as the West Kimberley and MacDonnell Ranges races are listed as vulnerable in Australia. Although the nominate lateralis was widespread and abundant at the time of European settlement,it subsequently declined dramatically, many local and regional populations, such as that on Depuch Island, becoming extinct. By 1970s, this subspecies was reduced to a few small scattered locations, with population extinctions continuing. Clearing of habitat for agriculture, and competition from introduced rabbits and from domestic and feral livestock (e.g. sheep and goats), as well as predation by introduced Red Fox (Vulpes vulpes) and domestic/feral cats (Felis catus), have all been implicated in the decline. Fox predation, however, has been demonstrated as a major cause of decline, many nominate lateralis populations recovering strongly when fox control was commenced in 1980s. Since 2010 some recovered populations have again declined, apparently as a consequence of habitat degradation caused by overgrazing and drought, as well as predation. Management of nominate lateralis populations includes ongoing fox and feral-goat control, reintroductions (six sites), supplementations to increase genetic diversity, and construction of predator-proof fencing around some populations. Long-term success of some management actions remains unclear. Although Barrow and Salisbury Island populations of nominate lateralis have not declined, they remain vulnerable to stochastic processes, the introduction of exotic predators, competitors, or weeds to the islands, or catastrophic wildfire. In addition, Barrow Island population has very low genetic diversity. Several recovery plans for this subspecies have been prepared. Endemic island subspecies pearsoni and hacketti have not declined and remain relatively common within their highly restricted island distributions, which are all protected areas with limited human access. They do, however, remain vulnerable to extinction through stochastic processes, the introduction of exotic predators, competitors, or weeds to the islands, or catastrophic wildfire. Additional populations of pearson: have been established on the South Australia islands of Middle and South Pearson (1960), Thistle (1974), and Wedge (1975). A 1974 introduction to WestIsland, also in South Australia, was unsuccessful. All populations of pearsoni have very low genetic diversity. The arid-adapted MacDonnell Ranges race of Black-footed Rock Wallaby has also declined greatly, particularly in the west and southern parts of its central Australian distribution. This major decline commenced in 1930s and isstill continuing, few populations now remaining in northern South Australia and eastern Western Australia. It is, however,still relatively common around Alice Springs, Northern Territory. Threats facing MacDonnell Ranges race are likely to include Red Fox and feral cat predation, habitat degradation caused by introduced herbivores (e.g. rabbits, feral donkeys, and camels), weeds, and altered fire regimes. In 1975, this race was reintroduced to Simpson’s Gap, in Northern Territory, where it became extinct in 1960s during drought. Current management strategies include fox and feral-animal control, weed and fire control, captive-breeding, and reintroductions. State and national recovery plans have been prepared. West Kimberley race is the least well-known of Black-footed Rock Wallaby taxa, and the extent of its current and historic distribution is unknown. Although it is locally common at somesites, it appears to have declined or become extinct at others (e.g. Mount Wynne). It does not occur in any protected areas and may be threatened by feral-cat predation, altered fire regimes, and habitat degradation due to grazing by cattle and feral donkeys. Red Fox is only occasionally reported in West Kimberley, and is not currently regarded as a major threat. Although specimens of nominate lateralis , hacketti, pearsoni and MacDonnell Ranges race have all been maintained in Australian zoos and research institutions, no Black-footed Rock Wallaby subspecies is well established in captivity. Additional research on taxonomy, distribution, abundance, dispersal, diet, reproduction, behavior, and impact and interaction of threats, as well as effectiveness of current threat-mitigation strategies, is required across the range of the species.

Bibliography. Abbott & Black (1978), Abbott & Burbidge (1995), Burbidge, Woinarski, Reed et al. (2008), Copley (1995), Copley & Alexander (1997), Copley et al. (1989), Eldridge (1997), Eldridge & Pearson (2008), Eldridge, Bell et al. (1992), Eldridge, Gee et al. (1994), Eldridge, King et al. (1999), Eldridge, Kinnear & Close (1994), Eldridge, Kinnear & Onus (2001), Eldridge, Kinnear, Zenger et al. (2004), Gibson (1999, 2000), Gould (1842b), Haouchar et al. (2013), Jones, Taggart & Temple-Smith (2004), Jones, Taggart, Temple-Smith & Eldridge (2011), Kinnear, Krebs et al. (2010), Kinnear, Onus & Bromilow (1988), Kinnear, Onus & Sumner (1998), Kinnear, Sumner & Onus (2002), Mason et al. (2011), Muhic et al. (2012), Pearson (1992, 2012), Pearson & Kinnear (1997), Read & Ward (2011), Robinson (1980), Robinson et al. (1996), Ruykys et al. (2011), Serventy (1953), Sharman et al. (1989), Thomas & Delroy (1971), Ward, Ruykys et al. (2011), Ward, Urban et al. (2011), Willers et al. (2011), Woinarski et al. (2014ap, 2014aq, 2014ar, 2014as, 2014at, 2104au).

Figures

On following pages: 29. Monjon (Petrogale burbidgel); 30. Proserpine Rock Wallaby (Petrogale persephone); 31. Yellow-footed Rock Wallaby (Petrogale xanthopus); 32. Rothschilds Rock Wallaby (Petrogale rothschild); 33. Black- footed Rock Wallaby (Petrogale lateralis).

Subspecies and Distribution. P.l.lateralisGould,1842—patchilyacrossSWesternAustralia,includingCapeRange,LittleSandyDesert,andthenearKellerberrininWheatbelt;alsoBarrowIandSalisburyI. P.l.hackettiThomas,1905—islandsofWilson,Mondrain,andWestall(RechercheArchipelago),WesternAustralia.Mayhaveoccurredhistoricallyalsoonadjacentmainland. P. l. pearson: Thomas, 1922 — North Pearson I, Investigator Group, South Australia. Introduced to South and Middle Pearson, Thistle, and Wedge Is, South Australia. A hitherto undescribed subspecies, the West Kimberley race, occurs (distributional limits uncertain) in Edgar, Grant, and Erskine Ranges and on Mt Wynne, Mt Anderson, and Mt Alexander, in S West Kimberley, Western Australia. A second undescribed subspecies, the MacDonnell Ranges race, is present in MacDonnell Ranges of C Australia, extending to E Western Australia and N South Australia.