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Hoolock

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GENUS HOOLOCK  (Mootnick and Groves, 2006)

Hoolock hoolock (Harlan, 1834). Hoolock or white-browed gibbon.   
General Description: The genus Hoolock has two species. Males have black hair with a pale brow that flicks up at the ends. Female pelage is copper-tan with dark-brown hair on the sides of the face, chest, and genital fringe. The female's face ring is wide above the eyes, turns upwards at the ends, and becomes thin as it encircles the muzzle. Shorter hairs on the sides of the neck give this gibbon's face a triangular appearance. The muzzle is larger compared to other gibbon species with a thin tuft of hair at the chin. The chest region is narrow. Ischial callosities are heavily furred. Infants' coats are grey-white with a yellow tinge (McCann, 1933); they eventually turn black. At puberty, females turn pale while males remain black throughout adult life. Hoolock gibbons produce a belching growl vocalization, the only gibbon species to do so (Mootnick, et al., 1987).  Occasionally, captive agile (H. agilis) and Mueller's gibbons (H. muelleri) have been misidentified as hoolock gibbons. This subgenus is characterized by a diploid chromosome number of 38 (Prouty, et al., 1983a, b).    Taxonomy: The hoolock gibbon is classified into two subspecies.

Hoolock hoolock (Groves, 1972). Western hoolock gibbon.  Area: Myanmar W of the Chindwin River, NortheasternSub-adult female H. hoolock, color-changing phase, at Borajan Reserve Forest, Assam, India, approximately 7 years old when photographed in October 2001. photo by Kashmira KakatiSub-adult female H. hoolock, color-changing phase, at Borajan Reserve Forest, Assam, India, approximately 7 years old when photographed in October 2001. photo by Kashmira Kakati subadult H. hoolock photo by M. DeeIndia, Bangladesh.   

Adult males have a long, black genital tuft and the white brow may be separated in its middle. Some males have slightly longer black hair under the brow and toward the center of the face, giving the appearance of a separated brow . Adult females of this subspecies have a distinct central part in the head hair. The hair of females' hands and feet are generally the same color as the body hair, but there is a black fringe on the fingers, toes, and the edge of the hands (Groves, 1972).

Hoolock leuconedys (Groves, 1967). Eastern hoolock gibbon.  Area: Myanmar E of the Chindwin River, southwestern Yunnan, and Lohit District, Arunachal Pradesh, northeast India.     male H. leuconedys photo by R. Wirth

female H. leuconedys photo by A. MootnickAdult males have black body hair with a brown cast, and the hair on the legs is usually black. Males have a separated brow. There is a white or brown genital tuft, and the chin hair is often grizzled with white-beige hairs. Adult females' hands and feet are slightly paler than are the limbs and may have a trace of white (Groves, 1972). Females' digits may have a trace of black on them. The female's crown hair grows slightly upwards and toward the nape of the neck and is not parted down the middle.

Good news for hoolock gibbons in their native Bangladesh,
from The Daily Star (Nov. 29, 2005):

Tree fellers turn forest protectors Innovative project stops illegal logging at Lawachara by ZAM Khairuzzaman
SHAMSER Ali, Shamim, Manik and Sujai, four former tree fellers of Doluchhara, dropped their axes and whipsaws about three months ago and have became active members of a 20-member community patrol team in the Lawachara National Park.  Their committed decision, part of an innovative government initiative, has helped effect a dramatic change in the nature reserve, 160-kilometres northeast of the capital city of Dhaka.    

"Illegal logging has stopped by 99 per cent," Ahad Ali, leader of the patrol team, told this scribe, who visited the previously shrinking forest recently. "Trees are now more safe here than ever before," Ahad said.  With a total area of about 1,531 hectares of Kamalganj and Srimangol upazilas in Moulvibazar district, Lawachara is famous for its abundant natural resources. But the National Park has been under threat from illegal logging over the last 30 years. Not only Lawachara, more than half of country's forest cover disappeared during that period.  But a new project of the Ministry of Environment and Forests -- with financing from USAID -- has intervened, turning a threatening trend into a protective process for the forest, at least at Lawachara.    

Inadequate manpower, lack of logistics and sometimes unscrupulous dealings used to prevent the Forest Department from protecting the trees. Taking advantage of the situation, at least five organised gangs were engaged in tree felling every day for timber. Moreover, as many as 250 people from the adjacent villages used to enter the forest to collect fuel wood, each gathering around 25 kilograms. Another 25 people took away bamboo from the forest each day, according to a survey conducted during May-July, 2004.  But now the forest is gaining protection through the Nishorgo Support Project (NSP), supporting improved management by the Forest Department in protected areas. The project has also helped increase the number of staff at Lawchara to halt poaching besides illegal logging.    

The ingenuity of the project involved motivating the surrounding villagers, including former tree fellers, to participate in forest patrolling. In return, project officials promised to help withdraw cases lodged by the Forest Department against the fellers and extend support to other actions to improve local people's livelihoods.    

The forest patrol team leader disclosed that each member of the team now receives Tk 50 per day from the NSP, which will be raised to Tk 75 shortly.  Soon, these cash payments are to be replaced by other livelihood improvement opportunities.  "We were jobless and had no source of income, but now we can see a ray of hope for a better future," Ahad said, adding that the NSP staffers helped form a samity (association) where they deposit Tk 10 every day. "Not only that, the NSP personnel helped open an account in a local bank in the name of the samity, where Tk 4,500 has been deposited till now," he said.    

Ahad's team is now given the charge of watching the southern part of Lawachara covering Chhonkhola, Segun Bagan and Akashmondi areas in shifts round the clock. Each member carries a stick. "We got a mobile phone, torch light and whistle for the purpose," he said. NSP senior manage (communication) Lutfun Nahar told that the patrol team members will be> provided with uniform with the NSP logo in the near future.    

The patrols have drastically reduced tree felling. According to the Lawchara Beat Office, Srimangol, 322 instances of tree felling were recorded before the fieldwork. But the number dropped to 107 instances at its very inception, and has almost stopped in the zones where other community patrolling has been enforced. At least 13 offenders were caught and handed over to the Forest Department personnel.    

The NSP official told that her organisation is developing alternative income-generating activities like cow rearing, fish culture, home gardening and other skill trainings to reduce poor people's dependence on the forest. At least 18 villagers were trained on cow rearing recently, she said.  A member of the patrol team, Abdul Hai, was also trained to perform in Gano Natoks, people's dramas, to create awareness and motivation about conservation of forests.    

NSP has formed a 50-member Co-Management Council to protect and regenerate Lawachara. The Council consists of 12 representatives from the local government institutions, nine representatives from the user groups, seven from the local elite, five from the resource owning group, three from the ethnic communities, two from the law enforcement authorities, two from the Forest Department, five from the non-governmental organisations (NGOs)/CBOs and five representatives from other government departments.    

NSP officials hope these first patrols are the just the beginning of something bigger.  Lutfun Nahar expressed her optimism that this initiative will be replicated also elsewhere and in the near future a massive people's movement will be created for protection of forests.