Pathom Yimkao. Ecology and conservation of the white-handed gibbon (Hylobates lar L.) in a tropical seasonal deciduous forest in Mae Hong Son province, Northern Thailand. Master's Degree(Environmental Biology). Mahidol University. : Mahidol University, 2009-07-09.
Ecology and conservation of the white-handed gibbon (Hylobates lar L.) in a tropical seasonal deciduous forest in Mae Hong Son province, Northern Thailand
นิเวศวิทยาและการอนุรักษ์ชะนีมือขาว (Hylobates lar L.) ในป่าผลัดใบเขตร้อน จังหวัดแม่ฮ่องสอน
Abstract:
This field study focused on the 1) distribution, 2) ranging, feeding and singing
behaviour, and 3) habitat structure, of the white-handed gibbon (H. lar) in a tropical
seasonal deciduous forest in Muang Phaem Forest, and 4) human impacts on gibbons and
5) the role of villagers and park staff in gibbon conservation. The study was conducted
from 26 February, 2004 to 26 February, 2005. About 87 individuals in six separate
populations of gibbons in Nam Lang basin were confirmed. Most gibbons inhabited
preserved and community forest nearby Karen villages. At least 3 gibbons died during the
study due to hunting. The main study group (G1) ranged within about 40-61 ha of
deciduous and bamboo forest with an average height of 23.50 m, ranging from 2-42 m
(SD= ±9.99) (n=264) and average dbh of 34.5 cm, ranging from 10-165.5 cm (SD=
±23.55) (n=381).
Group G1 spent most time around forest cliff sites, for rest, play, sleep and shelter.
Sometimes they visited pine-deciduous dipterocarp forest searching for food and singing.
Bamboo was frequently used by the group as a food source, sleeping place and travelling
route. Annual rainfall of 1,598 mm was recorded during the study. Minimum and
maximum temperature in the main study site ranged from 6-42 degrees Celsius. Group G1
was observed to feed on 29 species of plants. Eight other species have strong evidence of
being eaten by the gibbons. Thirteen species also recorded as being eaten by the gibbon in
other studies were present in the G1 home range. Nine species are classified as potential
food using local knowledge. Starting times of the first call (duet) of group G1 ranged from
06:47-10:45 h, but mostly from 07:45-08:15 h (13 times), 08:45-09:15 h (11 times) and
10:00-10:45 h (12 time) (n=61) during the whole study period. All groups started calling
later in winter. Among 3 ethnics groups including Karen, Lahu and Thai Yai (Shan),
Karen showed that their culture and tradition play a significant role in the survival of the
gibbons, and it is hoped to initiate gibbon conservation work in Muang Phaem Forest and
surrounding areas with Karen people. The role of wildlife sanctuaries in continuous
wildlife protection during the study period was unfortunately interrupted due mainly to
the transfer of the chief. Co-management between stakeholders and networking as sitebased
actions are suggested and considered necessary for gibbon conservation