Cercartetus nanus (Desmarest, 1818)

Russell A. Mittermeier & Don E. Wilson, 2015, Burramyidae, Handbook of the Mammals of the World – Volume 5 Monotremes and Marsupials, Barcelona: Lynx Edicions, pp. 436-455 : 454-455

5.

Eastern Pygmy Possum

Cercartetus nanus

French: Possum-loir de I'Est / German: Ostlicher Zwergbilchbeutler / Spanish: Pésum pigmeo oriental

Other common names: Common Dormouse-phalanger, Eastern Pygmy-possum

Taxonomy. Phalangista nana Desmarest, 1818,

“ I'tle Maria , située sur la cote est de la terre de Van Diémen [= Tasmania].”

Two subspecies are recognized.

Subspecies and Distribution.

C.n.nanusDesmarest,1818—TasmaniaandBassStraitIs(KingandFlinders).

C. n. unicolor Krefft, 1863 — mainland Australia, from the Queensland/New South Wales border down the E coast through S Victoria to SE South Australia.

Descriptive notes. Head-body 7-11 cm, tail 7.5-10.5 cm; weight 15-43 g. The Eastern Pygmy Possum can be distinguished from other species of pygmy possums byits size, coloration,tail length, and dentition. Fawn-gray fur dorsally, white below, the prehensile tail is about the same length as the body and is cylindrical, with thick fur at its base that becomes considerably sparserat its tip. P, is large,singly pointed, and double-rooted. A dark ring encircles each eye. The Eastern Pygmy Possum has very long whiskers that extend from eitherside ofits snout.

Habitat. Woodlands and heathlands from sea level to elevations of ¢.1800 m, mostly dominated by plants from the families Proteaceae and Myrtaceae , in particular Banksia and Eucalyptus , with grass trees (Xanthorrhoea) important for shelter. Populations of Eastern Pygmy Possums have been found in various habitats including rainforests, coastal forests, woodlands, and heathlands.

Food and Feeding. Eastern Pygmy Possums feed on nectar and pollen from tree species of Banksia , Eucalyptus , and Callistemon ; they also eat seeds, soft fruits, and invertebrates. Captive individuals are known to feed on spiders, termites, grasshoppers, beetles, and beetle larvae.

Breeding. Female Eastern Pygmy Possums can produce two or sometimes three litters of typically four young (but up to six have been recorded) during the breeding season in September—June, although there are regional differences (e.g. December—June in New South Wales and September—April in Victoria). Young emerge from the pouch at 30-40 days old, are weaned at c¢.63-65 days (weighing 9-11 g) and attain adult body mass at approximately 150 days. The young quickly reach sexual maturity and are able to breed in the wild as early as three months of age, when they weight about 16 g.

Activity patterns. Eastern Pygmy Possums are nocturnal and become active in their nests 4-40 minutes after sunset and leave the nest within one hour after sunset. During the day, they rest in various locations including cavities, rotten stumps, holes in the ground, unused bird nests, or dreys (nests) of ring-tailed possums (Pseudocheirus spp-), and within the thick vegetation of grass trees (Xanthorrhoea sp.). Tree genera with hollows used by Eastern Pygmy Possums include Banksia , Corymbia , Eucalyptus , and Syncarpia . They may also construct spherical nests from shredded bark or fresh leaves. They may also nest within accumulated pile of leaves in a hollow, on the ground, or under rocks. Eastern Pygmy Possums will sometimes go into torpor, during which body temperatures usually remain within 2-3°C above ambient temperature. When active, they spend most of their time in the midstory, inhabiting shrubby components of rainforests, sclerophyll forests, shrublands, heathlands, and woodlands.

Movements, Home range and Social organization. Male Eastern Pygmy Possums can have significantly larger short-term home ranges (0-24-1-68 ha) than females (0-18-0-61 ha), and they typically move over greater distances each night. Other studies have similarly found Eastern Pygmy Possums to occupy small home ranges of 0-06— 1-73 ha. Densities of Eastern Pygmy Possums are 2-5-20 ind/ha. Individuals have been recorded daily traversing 72-450 m of their home range at 10-98 m/h (average of 44 m/h for males and 35 m/h for females). Densities of Eastern Pygmy Possums are 2-5-20 ind/ha. Individuals have been recorded daily traversing 72-450 m oftheir home range at 10-98 m/h (average of 44 m/h for males and 35 m/h for females). In vegetation dominated by Banksia integrifolia and B. spinulosa, spool-and-line tracking revealed regular movements at a height of 1-2 m, while in rainforest where taller trees are more common they appear to climb higher in the canopy, more than 12 m above the ground. In other habitat such as heathland where trees are sparsely placed they primarily moves on the ground. Eastern Pygmy Possums will nest together on occasion; one study found that 41% of individuals nested with others, of which 48% were mothers and young. The largest group of non-maternal associations was of male— male groupings that included 46% of observations, followed by independent young at 36%, male-female groupings at 12%, and female—female groups at 6%. Longevity of Eastern Pygmy Possums has been recorded to be at least four years. Limited information in Victoria suggests that Eastern Pygmy Possums are promiscuous and normally solitary, with nests usually being occupied by single individuals. In contrast, other observations from New South Wales found nests typically occupied by more than one individual.

Status and Conservation. Classified as Least Concern on The IUCN Red List. The Eastern Pygmy Possum is susceptible to habitat loss from clearing, grazing, and fire regimes taking place at more frequent intervals or higher intensities than appropriate. Limited studies suggest that Eastern Pygmy Possums are particularly sensitive to habitat loss, after which capture rates show a dramatic decline and an almost total lack of juvenile and subadult recruitment into the population.

Bibliography. Bartholomew & Hudson (1962), Bladon et al. (2002), Bowen & Goldingay (2000), Carthew (1994), Dickman & Happold (1988), Dickman, Lunney & Menkhorst (2008), Harris (2006, 2008), Harris & Goldingay (2005), Harris, Goldingay et al. (2007), Harris, Gynther et al. (2007), Harris, Munks et al. (2007), Huang et al. (1987), Laidlaw & Wilson (1996), Sutherland et al. (2004), Tulloch (2004), Tulloch & Dickman (2006, 2007), Turner (1984a, 1984b), Ward (1990a), Westman & Geiser (2004).

Figures

1. Mountain Pygmy Possum (Burramys parvus), 2. Long-tailed Pygmy Possum (Cercartetus caudatus), 3. Western Pygmy Possum (Cercartetus concinnus), 4. Little Pygmy Possum (Cercartetus lepidus), 5. Eastern Pygmy Possum (Cercartetus nanus)

Subspecies and Distribution. C.n.nanusDesmarest,1818—TasmaniaandBassStraitIs(KingandFlinders). C. n. unicolor Krefft, 1863 — mainland Australia, from the Queensland/New South Wales border down the E coast through S Victoria to SE South Australia.