Ratufa bicolor (Sparrman, 1778)
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publication ID |
https://doi.org/ 10.5281/zenodo.6840226 |
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DOI |
https://doi.org/10.5281/zenodo.6818624 |
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persistent identifier |
https://treatment.plazi.org/id/064D0660-FFCE-ED34-FAF6-FE0EFD87F534 |
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treatment provided by |
Diego |
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scientific name |
Ratufa bicolor |
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Black Giant Squirrel
French: Ecureuil bicolore / German: Schwarzes Riesenhdrnchen / Spanish: Ardilla gigante negra
Other common names: Black-and-white Giant Squirrel, Malayan Giant Squirrel
Taxonomy. Sciurus bicolor Sparrman, 1778 ,
Anjer, West Java, Indonesia.
Eleven subspecies are recognized.
Subspecies and Distribution.
R.b.bicolorSparrman,1778—BaliandJavaincludingMaduraandKangeanIs(Saubi)offNEJava.
R.b.condorensisKloss,1921—ConSon1,offSVietnam.
R.b.felliThomas&Wroughton,1916—smallareainNMyanmar,S&EoftheChindwinRiver.
R.b.hainana].A.Allen,1906—HainanI,China.
R.b.palliataMiller,1902—SumatraandadjacentIndonesianislands(Bengkalis,Rupat,Tuangku,andTanahmasaIs).
R. b. smithi Robinson & Kloss, 1922 — W Vietnam and likely Cambodia and Laos. Subspecific affinity of populations on Belitung, Bangka, several Riau Is, and Natuna Is (Lagong, Lingung) are unclear. View Figure
Descriptive notes. Head-body 335-365 mm, tail 409-424 mm; weight 1.1-2 kg. The Black Giant Squirrel is a large black-and-white tree squirrel with a buff-to-white throat patch, or bib, and buff to white on sides of face. Buff throat and cheeks are separated by a black mustache-like mark. On dorsum, hair is black or sometimes frosted. On venter, pelage varies from creamy buff to orangish yellow. Island endemic subspecies condorensis is significantly smaller (head-body 305 mm, tail 324 mm) than other subspecies of the Black Giant Squirrel.
Habitat. Continuous tropical rainforests. The Black Giant Squirrel also occurs in mature evergreen and semi-evergreen broadleaf forests of Indochina and the Sunda Shelf.
Food and Feeding. The Black Giant Squirrel feeds on seeds and occasionally ingests fruit pulp, bark, sap, nectar, flowers, and leaves. Based on feeding time, squirrels fed extensively on seeds (61%) and pulp (20%); figs (Ficus, Moraceae) account for onehalf of pulp consumed. It does not cache food. Foraging is almost exclusively arboreal as the Black Giant Squirrel rarely descends to the ground.
Breeding. Breeding follows a mating chase, apparently involving one male and an estrous female. Litter size averages 1-4 (range 1-3 young) with a gestation period of 28-35 days, and females may have two litters per year. On Peninsular Malaysia, pregnant Ratufa were found between April and September, suggesting that parturition occurs at the beginning or during peak fruiting season.
Activity patterns. The Black Giant Squirrel is diurnal and lives most often above 20 m in the canopy, where it constructs a bolus drey of twigs and small branches in the crown of a tree. Dreys are constructed with long leafy twigs, some more than 31 m above the ground in the canopy, often on outermost branches of Koompassia (Fabaceae) or Shorea (Dipterocarpaceae) trees. Best predictor of nest location is height and girth of trees, with large mature trees favored. Nests do not appear to be lined with specific materials. Squirrels usually exited their nests in the morning, between 06:00 h and 08:00 h, but after rainy nights they might exit as late as 10:00 h. They were most active between dawn and 10:00 h, with a lesser peak of activity between 14:00 h and 16:00 h. Median time at which they reentered nests was 18:01 h. The crested serpent-eagle (Spilornis cheela) is a known predator.
Movements, Home range and Social organization. Population density of the Black Giant Squirrel was 11 ind/100 ha. Median rate of travel for individuals when foraging and feeding was 30 m/h, ranging from a median 65 m/h in the morning to 10 m/h at midday and 50 m/h at end of day. Estimated median for total distance traveled was 315 m/day. Home ranges were estimated to be 5-5-9 ha and individuals used 5-9 nests within their home range. During a study in Malaysia’s Kuala Lompat, Black Giant Squirrels lived in the middle and upper canopy, seldom below 20 m.
Status and Conservation. CITES Appendix II. Classified as Near Threatened on The IUCN Red List. The Black Giant Squirrel is in significant decline due to over-hunting and widespread habitat loss throughout much of its distribution. Population decline is strongly associated with reduction in canopy cover and tree density, as it nests in the high-canopy layer oftall trees.
Bibliography. Johnsingh & Manjrekar (2015), Moore & Tate (1965), Payne & Francis (1985), Saiful & Nordin (2004), Thorington et al. (2012).
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.
