Hoolocks are the second-largest of the gibbons, after the siamang. They reach a size of 60 to 90 cm and weigh 6 to 9 kg. The sexes are about the same size, but they differ considerably in coloration; males are black-colored with remarkable white brows, while females have a grey-brown fur, which is darker at the chest and neck. White rings around their eyes and mouths give their faces a mask-like appearance. The Oxford English Dictionary says that the name "hoolock" is from "a language of Assam."
Distribution
Range of the hoolock and other gibbons
In northeast India, the hoolock is found south of Brahmaputra and the North Bank areas and east of the Dibang Rivers.[4] Its range extends into seven states covering Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland, and Tripura (The seven northeastern states of India).[5][6] In Bangladesh, the western hoolock gibbons were distributed across 35 forest fragments. The largest of these (Lawachara and Kaptai) supported 42 and 84 individuals respectively, but 17 of the fragments had less than ten individuals. For a better overview the forest fragments are grouped into 13 areas. All areas are located within Chittagong and Sylhet divisions, mostly near the eastern border of the country. In China, in historical times, the skywalker gibbon was recorded in nine counties in the west bank of the Salween River in westernmost Yunnan province. Based on more recent interview surveys conducted in Oct-Nov 2008 and field surveys conducted in Mar, Apr, and Aug 2009, the current Chinese population of hoolock gibbons was found to be restricted to three counties (Baoshan, Tengchong, and Yingjiang). The population size was estimated to be less than 200 individuals. In Myanmar, all three species of hoolock gibbon can be found in the forested areas west of Thanlwin river. Of all four distribution countries, Myanmar holds the key population of all three species. [7]
Behaviour and diet
Like the other gibbons, they are diurnal and arboreal, brachiating through the trees with their long arms. They live together in monogamous pairs, which stake out a territory. Their calls serve to locate family members and ward off other gibbons from their territory. Their diet consists mainly of fruits, insects and leaves.
Breeding and lifecycle
Young hoolocks are born after a 7-month gestation, with milky white or buff-colored hair. After about 6 months, the hair of males darkens and turns black, while the females' hair remains buff-colored throughout their lives. After 8-9 years, they are fully mature and their fur reaches its final coloration. Their life expectancy in the wild is about 25 years.
Classification
Western hoolock gibbon
Call of hoolock gibbon from Hoollongapar Gibbon Sanctuary, Assam
The classification of this gibbon has changed several times in the past few years. Classically, all gibbons were classified in the genus Hylobates, with the exception of the siamang. After some studies, the genus was divided into three subgenera (including the siamang's Symphalangus), and then into four (recognizing Bunopithecus as the hoolock subgenus distinct from other gibbon subgenera). These four subgenera were elevated to full genus status. However, the type species for Bunopithecus is Bunopithecus sericus, an extinct gibbon or gibbon-like ape from Sichuan, China. Very recent investigations have shown that the hoolock gibbons are not closely related to B. sericus, so they have been placed in their own genus, Hoolock. In the process, the two subspecies of hoolock gibbons have been raised to species level.[1][2] A new subspecies of the western hoolock gibbon has been described recently from northeastern India, which has been named the Mishmi Hills hoolock gibbon, H. hoolock mishmiensis.[8] A further new species, H. tianxing, with an estimated population of about 200, was discovered in southwest China in 2017.[9]
^ abcMootnick, A.; Groves, C. P. (2005). "A new generic name for the hoolock gibbon (Hylobatidae)". International Journal of Primatology. 26 (4): 971–976. doi:10.1007/s10764-005-5332-4. S2CID 8394136.
^ abFan, P-F; He, K; Chen, X; Ortiz, A; Zhang, B; Zhao, C; Li, Y-Q; Zhang, H-B; Kimock, C; Wang, W-Z; Groves, C; Turvey, S.T; Roos, C; Helgen, K.M; Jiang, X-L (2017). "Description of a new species of Hoolock gibbon (Primates: Hylobatidae) based on integrative taxonomy" (PDF). American Journal of Primatology. 79 (9999): e22631. doi:10.1002/ajp.22631. ISSN 1098-2345. PMID 28073165. S2CID 3882019. (PDF) from the original on 2018-07-22. Retrieved 2019-02-01.
^Choudhury, A.U. (1987) Notes on the distribution and conservation of Phayre’s leaf monkey and Hoolock gibbon in India. Tigerpaper 14(2): 2-6
^Choudhury, A.U. (1991) Ecology of the Hoolock gibbon, a lesser ape in the tropical forests of North-eastern India. J. Tropical Ecology 7: 147-153. Cambridge.
^Choudhury, A.U. (2006) The distribution and status of hoolock gibbon, Hoolock hoolock, in Manipur, Meghalaya, Mizoram, and Nagaland in Northeast India. Primate Conservation 20: 79-87
^Geissmann, T., Grindley, M. E., Ngwe Lwin, Saw Soe Aung, Thet Naing Aung, Saw Blaw Htoo, and Momberg, F. (2013). The conservation status of hoolock gibbons in Myanmar. Gibbon Conservation Alliance, Zürich, Switzerland, xii + 157 pp
^Choudhury, A. U. (2013). "Description of a new subspecies of hoolock gibbon Hoolock hoolock from North East India". The Newsletter & Journal of the Rhino Foundation for Nat. In NE India. 9: 49–59.
^ abBrown, Georgia (11 January 2017). "New species of gibbon discovered in China". The Guardian. from the original on 27 April 2019. Retrieved 11 January 2017.
External links
Wikispecies has information related to Hoolock gibbon.
Wikimedia Commons has media related to Hoolock.
ARKive -
Hoolock gibbon photos
Hoolock gibbon songs
Gibbon Conservation Center
Primate Info Net Hoolock factsheet
March 05, 2023
hoolock, gibbon, hoolock, gibbons, three, primate, species, genus, hoolock, gibbon, family, hylobatidae, native, eastern, bangladesh, northeast, india, myanmar, southwest, china, scientific, classificationkingdom, animaliaphylum, chordataclass, mammaliaorder, . The hoolock gibbons are three primate species of genus Hoolock in the gibbon family Hylobatidae native to eastern Bangladesh Northeast India Myanmar and Southwest China Hoolock gibbons 1 2 Scientific classificationKingdom AnimaliaPhylum ChordataClass MammaliaOrder PrimatesSuborder HaplorhiniInfraorder SimiiformesFamily HylobatidaeGenus HoolockMootnick amp Groves 2005SpeciesHoolock hoolock Hoolock leuconedys Hoolock tianxing 3 Contents 1 Description 2 Distribution 3 Behaviour and diet 4 Breeding and lifecycle 5 Classification 6 References 7 External linksDescription EditHoolocks are the second largest of the gibbons after the siamang They reach a size of 60 to 90 cm and weigh 6 to 9 kg The sexes are about the same size but they differ considerably in coloration males are black colored with remarkable white brows while females have a grey brown fur which is darker at the chest and neck White rings around their eyes and mouths give their faces a mask like appearance The Oxford English Dictionary says that the name hoolock is from a language of Assam Distribution Edit Range of the hoolock and other gibbons In northeast India the hoolock is found south of Brahmaputra and the North Bank areas and east of the Dibang Rivers 4 Its range extends into seven states covering Arunachal Pradesh Assam Manipur Meghalaya Mizoram Nagaland and Tripura The seven northeastern states of India 5 6 In Bangladesh the western hoolock gibbons were distributed across 35 forest fragments The largest of these Lawachara and Kaptai supported 42 and 84 individuals respectively but 17 of the fragments had less than ten individuals For a better overview the forest fragments are grouped into 13 areas All areas are located within Chittagong and Sylhet divisions mostly near the eastern border of the country In China in historical times the skywalker gibbon was recorded in nine counties in the west bank of the Salween River in westernmost Yunnan province Based on more recent interview surveys conducted in Oct Nov 2008 and field surveys conducted in Mar Apr and Aug 2009 the current Chinese population of hoolock gibbons was found to be restricted to three counties Baoshan Tengchong and Yingjiang The population size was estimated to be less than 200 individuals In Myanmar all three species of hoolock gibbon can be found in the forested areas west of Thanlwin river Of all four distribution countries Myanmar holds the key population of all three species 7 Behaviour and diet EditLike the other gibbons they are diurnal and arboreal brachiating through the trees with their long arms They live together in monogamous pairs which stake out a territory Their calls serve to locate family members and ward off other gibbons from their territory Their diet consists mainly of fruits insects and leaves Breeding and lifecycle EditYoung hoolocks are born after a 7 month gestation with milky white or buff colored hair After about 6 months the hair of males darkens and turns black while the females hair remains buff colored throughout their lives After 8 9 years they are fully mature and their fur reaches its final coloration Their life expectancy in the wild is about 25 years Classification Edit Western hoolock gibbon source source Call of hoolock gibbon from Hoollongapar Gibbon Sanctuary Assam The classification of this gibbon has changed several times in the past few years Classically all gibbons were classified in the genus Hylobates with the exception of the siamang After some studies the genus was divided into three subgenera including the siamang s Symphalangus and then into four recognizing Bunopithecus as the hoolock subgenus distinct from other gibbon subgenera These four subgenera were elevated to full genus status However the type species for Bunopithecus is Bunopithecus sericus an extinct gibbon or gibbon like ape from Sichuan China Very recent investigations have shown that the hoolock gibbons are not closely related to B sericus so they have been placed in their own genus Hoolock In the process the two subspecies of hoolock gibbons have been raised to species level 1 2 A new subspecies of the western hoolock gibbon has been described recently from northeastern India which has been named the Mishmi Hills hoolock gibbon H hoolock mishmiensis 8 A further new species H tianxing with an estimated population of about 200 was discovered in southwest China in 2017 9 The species of hoolock are 2 9 Western hoolock gibbon H hoolock Eastern hoolock gibbon H leuconedys Skywalker hoolock gibbon H tianxing 3 References Edit a b Groves C P 2005 Order Primates In Wilson D E Reeder D M eds Mammal Species of the World A Taxonomic and Geographic Reference 3rd ed Johns Hopkins University Press pp 178 179 ISBN 978 0 8018 8221 0 OCLC 62265494 a b c Mootnick A Groves C P 2005 A new generic name for the hoolock gibbon Hylobatidae International Journal of Primatology 26 4 971 976 doi 10 1007 s10764 005 5332 4 S2CID 8394136 a b Fan P F He K Chen X Ortiz A Zhang B Zhao C Li Y Q Zhang H B Kimock C Wang W Z Groves C Turvey S T Roos C Helgen K M Jiang X L 2017 Description of a new species of Hoolock gibbon Primates Hylobatidae based on integrative taxonomy PDF American Journal of Primatology 79 9999 e22631 doi 10 1002 ajp 22631 ISSN 1098 2345 PMID 28073165 S2CID 3882019 Archived PDF from the original on 2018 07 22 Retrieved 2019 02 01 Choudhury A U 1987 Notes on the distribution and conservation of Phayre s leaf monkey and Hoolock gibbon in India Tigerpaper 14 2 2 6 Choudhury A U 1991 Ecology of the Hoolock gibbon a lesser ape in the tropical forests of North eastern India J Tropical Ecology 7 147 153 Cambridge Choudhury A U 2006 The distribution and status of hoolock gibbon Hoolock hoolock in Manipur Meghalaya Mizoram and Nagaland in Northeast India Primate Conservation 20 79 87 Geissmann T Grindley M E Ngwe Lwin Saw Soe Aung Thet Naing Aung Saw Blaw Htoo and Momberg F 2013 The conservation status of hoolock gibbons in Myanmar Gibbon Conservation Alliance Zurich Switzerland xii 157 pp Choudhury A U 2013 Description of a new subspecies of hoolock gibbon Hoolock hoolock from North East India The Newsletter amp Journal of the Rhino Foundation for Nat In NE India 9 49 59 a b Brown Georgia 11 January 2017 New species of gibbon discovered in China The Guardian Archived from the original on 27 April 2019 Retrieved 11 January 2017 External links Edit Wikispecies has information related to Hoolock gibbon Wikimedia Commons has media related to Hoolock ARKive images and movies of the hoolock gibbon Bunopithecus hoolock Hoolock gibbon photos Hoolock gibbon songs Gibbon Conservation Center Hoolock gibbon photos taken in the wild Primate Info Net Hoolock factsheet Retrieved from https en wikipedia org w index php title Hoolock gibbon amp oldid 1142864484, wikipedia, wiki, book, books, library,
