Phalanger orientalis (Pallas, 1766)

Russell A. Mittermeier & Don E. Wilson, 2015, Phalangeridae, Handbook of the Mammals of the World – Volume 5 Monotremes and Marsupials, Barcelona: Lynx Edicions, pp. 456-497 : 491

17.

Northern Common Cuscus

Phalanger orientalis

French: Phalanger gris / German: Nordlicher Grauer Kuskus / Spanish: Cuscus septentrional

Other common names: Common Phalanger, Grey Cuscus

Taxonomy. Didelphidis orientalis Pallas, 1766 ,

“ Amboyna ” (= Ambon Island, Moluccas, Indonesia).

Subfossil records from a handful of islands (New Ireland Island in the Bismarcks, Buka Island in the Solomons, and Timor in the Lesser Sundas) demonstrate that this species has been widely introduced by humans to islands where it is not part of the original, native fauna (in some cases going back 10000-20000 years before the present), both east and west ofits original distribution in New Guinea (and perhaps New Britain Island, likely to be the original homeland of the subspecies breviceps). Two subspecies recognized.

Subspecies and Distribution.

P.o.orientalisPallas,1766—W&NNewGuineafromtheBird’sHead(=Vogelkop)PeninsulatotheLaearea,andadjacentislands(Waigeo,Batanta,Salawati,Misool,Yapen,Biak,Supiori,Numfor,SuMios,Karkar,Bagabag,[.ong,andVokeo),alsointheC&SMoluccasandELesserSundas(Seram,Ambon,Buru,Saparua,Gorong,Banda,Kai,andBabarIs),mostlikelyintroducedbyhumansinseveralotherislands(Timor,Wetar,andLet).

P. o. breviceps Thomas, 1888 — likely native to New Britain I in the Bismarck Archipelago, but distributed throughout the Bismarck Archipelago and Solomon Is, apparently mostly by human-mediated introduction (Umboi, Duke of York, New Ireland, Lihir, Tabar, Boang, Manus, Nissan, Buka, Bougainville, Alu, Fauro, Mono, Vella Lavella, New Georgia, Ganongga, Gatukai, Rendova, Molakobi, Komachu, Choiseul, Ysabel, Russell, Guadalcanal, Malaita, and Makira Is).

Descriptive notes. Head—body 30-50 cm, tail 28-42.5 cm; weight 1.6-5 kg. Due to the remarkable variability of the Northern Common Cuscus throughoutits distribution (especially size, e.g. condylobasal length 68-96 mm, and color), it can be difficult to identify. Typically, it is large and sexually dimorphic (males larger) and has short, slightly coarse coat and typically has dark dorsal stripe. Island populations can vary from being all white (especially Moluccas) to dark chocolate brown or blackish (especially at highest elevations in the Solomon Islands). On mainland New Guinea, male Northern Common Cuscuses are grayish, females are more reddish brown, and juveniles are reddish or gray. Females generally have white tail tip. There is no prominent diastema between upper canine and incisor. Secator (large upper premolar) is variable in size but relatively small compared with other large New Guinean species of Phalanger .

Habitat. Variety of forested habitats, including primary mossy forest and other primary forests, and old gardens. The Northern Common Cuscus is a widespread and occurs from sea level up to elevations of ¢.1500 m in New Guinea (occurring higher in some of its insular distribution in the absence of other congeners). Anecdotal observations suggest that the Northern Common Cuscus can be more common in some gardens with greater concentrations of edible plants than in primary forest.

Food and Feeding. For such a widespread species, diets of Northern Common Cuscuses have been poorly studied, but it appears to be folivorous—frugivorous. It also feeds on bark. Fruits of the tree genera Diospyros , Eugenia , Pandanus , and Gnetum have been recorded in the diet. There are observations of the Northern Common Cuscus, the Ground Cuscus ( P. gymnotis ), and Stein’s Cuscus ( P. vestitus ) congregating at fruiting trees of Lithocarpus (Fagaceae) .

Breeding. Twin Northern Common Cuscuses have been recorded and may be the modal number of young produced. Young have been recorded in March, May, June, July, October, and November, suggesting little or no seasonality in breeding.

Activity patterns. There is no specific information available for this species, but the Northern Common Cuscus is no doubt nocturnal and sleeps in arboreal dens.

Movements, Home range and Social organization. There is no specific information available for this species, but Northern Common Cuscus may communicate with a call that sounds like a small dog.

Status and Conservation. CITES Appendix II. Classified as Least Concern on The [UCN Red List. The Northern Common Cuscus has a wide distribution and a very large overall population. It is tolerant of some habitat degradation, and has been very widely introduced into areas where it is not native.

Bibliography. Flannery (1995a, 1995b), Flannery & White (1991), Heinsohn (2003), Liem (1983), Menzies & Pernetta (1986).

Figures

11. Peleng Cuscus (Phalanger pelengensus), 12. Moluccan Cuscus (Phalanger ornatus), 13. Gebe Cuscus (Phalanger alexandrae), 14. Obi Cuscus (Phalanger rothschildi), 15. Ground Cuscus (Phalanger gymnotis), 16. Woodlark Cuscus (Phalanger lullulae), 17. Northern Common Cuscus (Phalanger orientalis), 18. Eastern Common Cuscus (Phalanger intercastellanus), 19. Southern Common Cuscus (Phalanger mimicus), 20. Telefomin Cuscus (Phalanger matanim), 21. Stein’s Cuscus (Phalanger vestitus), 22. Silky Cuscus (Phalanger sericeus), 23. Mountain Cuscus (Phalanger carmelitae), 24. Black Spotted Cuscus (Spilocuscus rufoniger), 25. Waigeo Spotted Cuscus (Spilocuscus papuensis), 26. Admiralty Spotted Cuscus (Spilocuscus kraemeri), 27. Blue-eyed Spotted Cuscus (Spilocuscus wilsoni), 28. Common Spotted Cuscus (Spilocuscus maculatus), 29. Australian Spotted Cuscus (Spilocuscus nudicaudatus)

Subspecies and Distribution. P.o.orientalisPallas,1766—W&NNewGuineafromtheBird’sHead(=Vogelkop)PeninsulatotheLaearea,andadjacentislands(Waigeo,Batanta,Salawati,Misool,Yapen,Biak,Supiori,Numfor,SuMios,Karkar,Bagabag,[.ong,andVokeo),alsointheC&SMoluccasandELesserSundas(Seram,Ambon,Buru,Saparua,Gorong,Banda,Kai,andBabarIs),mostlikelyintroducedbyhumansinseveralotherislands(Timor,Wetar,andLet). P. o. breviceps Thomas, 1888 — likely native to New Britain I in the Bismarck Archipelago, but distributed throughout the Bismarck Archipelago and Solomon Is, apparently mostly by human-mediated introduction (Umboi, Duke of York, New Ireland, Lihir, Tabar, Boang, Manus, Nissan, Buka, Bougainville, Alu, Fauro, Mono, Vella Lavella, New Georgia, Ganongga, Gatukai, Rendova, Molakobi, Komachu, Choiseul, Ysabel, Russell, Guadalcanal, Malaita, and Makira Is).