Black giant squirrel
| Black giant squirrel | ||||||||||||
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Black giant squirrel ( Ratufa bicolor ) in Khao Yai National Park, Pak Chong, Thailand |
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| Scientific name | ||||||||||||
| Ratufa bicolor | ||||||||||||
| ( Sparrman , 1778) |
The black giant squirrel ( Ratufa bicolor ) is a type of squirrel from the genus of the giant squirrel ( Ratufa ). It occurs in South and Southeast Asia from the south of the People's Republic of China over parts of India to the Southeast Asian islands of Indonesia .
features
With a head-torso length of 36 to 43 centimeters and a weight of around 1300 to 2300 grams, the black giant squirrel is one of the largest species of squirrel in the world. The tail reaches a length of 40 to 51 centimeters and is thus slightly longer than the rest of the body. The rear foot becomes 84 to 91 millimeters long, the ear reaches a length of 30 to 38 millimeters. The coloring of the animals is very variable and can be very different from region to region. The back fur, the head and the tail are usually completely black, only the nose and the muzzle are white and the animals have a sand-colored eye ring. The belly side is also sand-colored to rusty yellow.
| 1 | · | 0 | · | 1 | · | 3 | = 20 |
The skull has a total length of 71 to 77 millimeters. Like all species of the genus has the type in the upper jaw half per one to a incisor tooth formed incisor (incisor) to which a tooth gap ( diastema follows). This is followed by a premolar and three molars . The teeth in the lower jaw correspond to those in the upper jaw. In total, the animals have a set of 20 teeth.
distribution
The black giant squirrel is found in South and Southeast Asia from the south of the People's Republic of China over parts of India to the Southeast Asian islands of Indonesia . In China the species comes as a subspecies R. b. gigantea in the south of the provinces of Yunnan and Guanxi and as a subspecies R. b. hainana on Hainan Island . From here the distribution area extends south into the Indian states of Assam , Arunachal Pradesh , Meghalaya , Nagaland and West Bengal and the east of Nepal , Bhutan and Bangladesh . In Southeast Asia it extends through Myanmar , Thailand , Laos , Cambodia , Vietnam and the Malay Peninsula to the Indonesian islands of Sumatra , Java , Bali , Panaitan , Belitung and the Mentawai Islands .
The altitude distribution is between 500 and 2500 meters.
Way of life
Like all species of the genus, the black giant squirrel is largely arboricolous and lives in the tropical rainforests and dry mountain forests of the range. It is diurnal and a good climber, and it can make long jumps of more than six meters. As a rule, the species moves stalking over the branches with its tail hanging. It usually avoids the ground and only climbs down from the trees when it drives away another squirrel or when the males pursue a female during the mating season. Occasionally, however, the black giant squirrel eats food on the ground. Most of the time the animals live solitary or in pairs, they use tree hollows as hiding places. The diet consists of fruits, nuts, various tree and shrub bark, as well as insects and bird eggs. Especially on the Malay Peninsula, the species is in competition with numerous other tree-living mammals and birds that also feed on fruits.
During the breeding season, the animals build large nests out of leaves, branches and twigs. The females give birth to the young in the nests, whereby a litter consists of one to three young. The gestation period is 28 to 35 days and the females can reproduce up to twice a year, once in spring and once in autumn.
Systematics
The black giant squirrel is classified as an independent species within the genus of the giant squirrel ( Ratufa ), which consists of four species. The first scientific description comes from Anders Sparrman from 1778, who described an individual from the area of Anyer in the west of the island of Java .
The species is likely to form a complex of several closely related species, the exact species division and taxonomy being under discussion and research. In addition to the nominate form, several other subspecies are distinguished within the species , which in turn have numerous synonyms :
| subspecies | First describer | Synonyms |
|---|---|---|
| R. b. bicolor | Sparrman (1778) | albiceps, baliensis, humeralis, javensis, leschnaultii, major, sondaica |
| R. b. condorensis | Kloss (1920) | - |
| R. b. felli | Thomas and Wroughton (1916) | - |
| R. b. gigantea | McClelland (1839) | lutrina, macruroides |
| R. b. hainana | JA Allen (1906) | stigmosa |
| R. b. leucogenys | Kloss (1916) | Sine |
| R. b. melanopepla | Miller (1900) | anambae, angusticeps, dicolorata, fretensis, penangensis, peninsulae, tiomanensis |
| R. b. palliata | Miller (1902) | batuana, laenata |
| R. b. phaeopepla | Miller (1913) | celaenopepla, marana |
| R. b. smithi | Robinson and Kloss (1922) | - |
According to Torrington et al. In 2012, R. b. angusticeps regarded as an independent subspecies and not with R. b. melanopepla synonymized .
Status, threat and protection
The black giant squirrel population in South and Southeast Asia is clearly declining, although the degree of population decline is not known. The species occurs regularly in Laos, Thailand and Vietnam, especially in regions where hunting is regulated and controlled. In contrast, it quickly disappears in fragmented areas. In Laos in particular, the decline is so high that the species can no longer be detected in current recordings in many areas where it was previously found and is accordingly rare. It is still common in Cambodia, but is less common in Malaysia. In Java in particular, populations are declining and the species is only found in remote regions in residual forests, with the populations continuing to decline with the loss of habitat due to deforestation.
The main threats to the black giant squirrel include habitat loss due to the conversion of forest areas into agricultural land, deforestation and logging, forest fires and the expansion of human settlement. In addition, there is the hunt for the animals as a meat supplier in large parts of the distribution area. This applies to China, Laos, Vietnam and Thailand. In Vientiane , the animal used to be one of the most common fresh meat supply mammals on the market. An increase in hunting is assumed for Cambodia, as larger mammals are now being hunted down to smaller ones. Hunting is forbidden in Java, but stocks are declining here due to habitat loss.
The black giant squirrel is classified as Near Threatened by the International Union for Conservation of Nature and Natural Resources (IUCN). The reason is the clear decline in populations due to overhunting and the very strong loss of habitat of the species in most of its range. In China, the animals are classified as threatened and protected. The species occurs in several nature reserves within the range, and it is also subject to species protection in accordance with the Washington Convention on the Protection of Species , in which it is listed as a species in need of protection in Appendix II.
literature
- Robert S. Hoffmann, Andrew T. Smith: Black Giant Squirrel. In: Andrew T. Smith , Yan Xie: A Guide to the Mammals of China. Princeton University Press, Princeton NJ 2008, ISBN 978-0-691-09984-2 , p. 173.
- Richard W. Thorington Jr. , John L. Koprowski, Michael A. Steele: Squirrels of the World. Johns Hopkins University Press, Baltimore MD 2012, ISBN 978-1-4214-0469-1 , pp. 25-26 .
Web links
- Ratufa bicolor inthe IUCN 2013 Red List of Threatened Species . Listed by: J. Walston, JW Duckworth, S. Molur, 2008. Retrieved February 7, 2014.
supporting documents
- ↑ a b c d e f g Robert S. Hoffmann, Andrew T. Smith: Black Giant Squirrel. In: Andrew T. Smith , Yan Xie: A Guide to the Mammals of China. Princeton University Press, Princeton NJ 2008, ISBN 978-0-691-09984-2 , p. 173.
- ^ Robert S. Hoffmann, Andrew T. Smith: Ratufa. In: Andrew T. Smith , Yan Xie: A Guide to the Mammals of China. Princeton University Press, Princeton NJ 2008, ISBN 978-0-691-09984-2 , p. 173.
- ↑ a b c d e f g h i j k l Ratufa bicolor in the Red List of Threatened Species of the IUCN 2013.2. Listed by: J. Walston, JW Duckworth, S. Molur, 2008. Retrieved February 7, 2014.
- ↑ a b Richard W. Thorington Jr. , John L. Koprowski, Michael A. Steele: Squirrels of the World. Johns Hopkins University Press, Baltimore MD 2012, ISBN 978-1-4214-0469-1 , pp. 25-26 .
- ↑ a b c Ratufa bicolor In: Don E. Wilson , DeeAnn M. Reeder (Ed.): Mammal Species of the World. A taxonomic and geographic Reference. 2 volumes. 3. Edition. Johns Hopkins University Press, Baltimore MD 2005, ISBN 0-8018-8221-4 .