Onychogalea fraenata (Gould, 1840)

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 : 695

8.

Bridled Nail-tailed Wallaby

Onychogalea fraenata

French: Wallaby bridé / German: Nagelschwanzkanguru / Spanish: Ualabi de cola de una meridional

Other common names: Bridled Nailtail Wallaby, Bridled Nail-tail Wallaby, Bridled Wallaby, Flashjack, Merrin, Waistcoat Wallaby

Taxonomy. Macropus frenatus Gould, 1841 ,

“ Interior of New South Wales ,” Australia.

This species is monotypic.

Distribution. Confined to Taunton National Park, near Dingo, W of Rockhampton, EC Queensland.

Descriptive notes. Head-body 42-3— 109 cm (males) and 34.5-61.3 cm (females), tail 41.2-57.5 cm (males) and 32.5-46.5 cm (females); weight 2-8 8. 3 kg (males) and 1.8-5 kg (females). Grayish brown dorsally, paler light gray to white ventrally and on flanks. Limbs paler than body, although digits black. Head, shoulders, and upper arms often more rufous. Pale cheek stripe below indistinct dark stripe from nose to eye. Ears long and pointed, pale inside and on edges, dark gray outside. Distinct dark mid-dorsal stripe from forehead to upper back, widest on neck and upper back. Prominent extended crescent-shaped white stripe running from base of ears across shoulders to underarms, contrasting with dark dorsal coloring from between ears to upper back. Tail paler ventrally, with a distal short dorsal crest of short dark hairs; distinctive short, dark, spur-like horny projection on end oftail. Diploid chromosome number is 18.

Habitat. Grassy woodland and shrubland. Now confined to a mosaic of open eucalypt woodland and brigalow ( Acacia harpophylla , Fabaceae ) scrub. Preferred habitat appears to be the ecotone between dense shrubland and open woodland.

Food and Feeding. Feeds on leaves and stems of a diversity of forbs, grasses, chenopods, plants with stellate trichomes ( Malvaceae , Solanaceae , and Tiliaceae ), sedges, and browse. Soft herbaceous species (forbs and malvaceous plants) are favored, but dietary breadth increases in dry conditions, when significantly more browse and grass are eaten. Seeds, fruits, and flowers are also sometimes consumed.

Breeding. Females reach sexual maturity from 4-5 months and males at about nine months. Breeding occurs throughout year, females producing one young per pregnancy. The estrous cycle is 30-45 (mean 36) days and the gestation period is 21-26 (mean 24) days. Females exhibit embryonic diapause. No post-partum mating has been observed, but females come into estrus and mate when incumbent pouch young is approximately three months old. Young conceived at this mating is then born typically within three hours (but up to two days) of the pouch being vacated by previous young. Young spends about four months in pouch. Immediately following permanent pouch emergence mothers hide their young in low, dense vegetation during day, usually more than 200 m from their own diurnal shelter. Females return to the young at dusk to suckle until they are weaned, by six months, after which they rapidly become independent. Mating system is promiscuous, both sexes mating with multiple partners. Males compete intensely for access to females. An estrous female may attract up to six males, but only those of more than 5-6 kg gain mating access. Copulation can last for more than 90 minutes, then the dominant male guards the female from rival males for a day or two. Typically, only 25% of resident males, mostly dominant individuals with large home ranges, achieve paternity. Females in better body condition are more likely to produce sons.

Activity patterns. Primarily nocturnal. Shelters during day under dense shrubs or grass tussocks, or sometimes in hollow logs. Will also shelter at base of trees or near fallen branches. Individuals have multiple shelter sites in their home range and reuse them regularly, although they are also, rarely, used by different individuals. Becomes active about an hour before dusk and starts to move toward more open areas to forage. Rarely ventures more than 200 m from dense vegetation, except during drought. In winter will bask in the sun at edge of scrub, before moving into open areas to feed. Returns to shelter around sunrise, but usually earlier during wet season. Avoids detection by lying prone on ground or crawling away to hide under bushes and remaining motionless, even when closely approached. When flushed, hops rapidly into dense vegetation or may take refuge in a hollow log.

Movements, Home range and Social organization. Primarily solitary, although feeding aggregations of up to five individuals can occur. Home ranges averaged 59 ha for males and 26 ha for females (95% harmonic mean) in one study, and 53 ha for males and 23 ha for females (95% minimum convex polygon) in another study. Home ranges overlap both within and between sexes, although the area containing diurnal shelter sites may be defended. Male home ranges typically overlap those of several females.

Status and Conservation. CITES Appendix I. Classified as Endangered on The IUCN Red Lust. Listed also as endangered in Australia. Although this species was formerly widespread and abundant on western slopes and plains of south-east Australia from Charters Towers, east Queensland, south to north-west Victoria, it declined throughout its range following European settlement and by late 1930s was thought extinct. This rapid decline was associated with establishment of the pastoral (sheep and cattle) industry throughout its range, which presumably resulted in competition and/ or habitat degradation. Loss of habitat due to widespread clearing for agriculture, altered fire regimes, and predation by introduced Red Fox (Vulpes vulpes) and domestic/feral cats (Felis catus) likely also to have been significant agents of decline in some areas. In 1973, a small population of Bridled Nail-tailed Wallabies was rediscovered in central Queensland. The area supporting this remnant population was subsequently acquired as a reserve, and the number of wallabies increased following exclusion of cattle; during 1990s drought, however, numbers declined significantly, and are yet to recover fully. This macropodid continues to be threatened by introduced predators, habitat modification, including spread of introduced buftelgrass ( Cenchrus ciliaris, Poaceae ), and environmental stochasticity (e.g. drought, wildfire, disease). Several recovery plans have been prepared and some potential threats are being controlled. A captive-breeding program was set up in 1991 and the species is now well established in captivity. Captive-bred and wild-caught individuals have been reintroduced to two sites in central Queensland, becoming well established at one (Idalia National Park, started in 1993) but less secure at the other (Avocet Nature Refuge, started in 2001). An attempt to introduce these wallabies in western New South Wales was unsuccessful owing to Red Fox predation. Additional research on the impact of disease and on threat abatementis required.

Bibliography. Curtis (2012), Dawson et al. (1992a, 1992b), Evans (1992, 1996), Evans & Gordon (2008), Evans & Jarman (1999), Fisher (1999, 2000), Fisher & Goldizen (2001), Fisher & Lara (1999), Fisher et al. (2001), Gordon & Lawrie (1980), Hayman (1989), Hayward et al. (2012), Horsup & Evans (1993), Johnson (1997 2003), Kingsley et al. (2012), Lundie-Jenkins & Lowry (2005), McKnight (2008e), Menkhorst & Knight (2001), Pople et al. (2001), Sigg & Goldizen (2006), Sigg et al. (2005), Tierney (1985), Woinarski et al. (2014ah).

Figures

On following pages: 4. Grey Forest Wallaby (Dorcopsis luctuosa); 5. Brown Forest Wallaby (Dorcopsis muelleri); 6. Macleay’s Forest Wallaby (Dorcopsulus macleayi); 7. Small Forest Wallaby (Dorcopsulus vanheurni); 8. Bridled Nail-tailed Wallaby (Onychogalea fraenata); 9. Northern Nail-tailed Wallaby (Onychogalea unguifera).

Distribution. Confined to Taunton National Park, near Dingo, W of Rockhampton, EC Queensland.