Sunday, March 25, 2012

Western Macaque Sub-species in Bhutan

Macaca assamensis pelops:  Western Macaque Sub-species in Bhutan

The Western Macaque sub-species (Macaca assamensis pelops) commonly known as Western Macaque was observed in July 2011 in Bhutan although central Bhutan was believed to be the range for the species. Mr. Rinchen Wangdi sighted about 8 individuals on the road about 2 km away from Bji Zam towards Trongsa Dzong in Trongsa District on 11th July 2011 afternoon (2:17 pm, BST). It is located at an altitude of 6203 ft and 27o30’59.20’’ North and 90o27’53.36’’ East on GPS reading.
The habitat is dominated by Oak forest (Quercus griffithii) associated with Castanopsis indica, Rhus spp., Rhododendron arboreum, Lyonia ovalifolia, with dominant under story of Elaeagnus spp. and Artemisia vulgaris. Above the road in the marshes, some pioneer species like Alnus nepalensis were seen regenerating adequately. The gradient of the site is moderately sloped (<40o) facing east aspect.

Morphological characteristics of Western Macaque  (Macaca assamensis pelops)
The male photographed was heavily built. The pelage is long and thick giving him almost a shaggy look. When seen at closer look it appears quit frightening due to its fierceness in nature. The light coat pelage colour is uniform at dorsal and becomes much paler underneath. It has unique characteristics of dark crown patch and a pale collared hair around the neck. It significantly lacks facial markings. It was also observed that the moustache appearance is less prominent. The facial skin is darker than dorsal coat with upper portion of face relatively boarder than muzzle. The tail is short with same colour as dorsal coat and has almost rounded tail tip.
 Photo by: Rinchen Wangdi, July 2011 

Owing to limited access for references on the species, an extensive online internet services were used besides few books. For more confirmation, the copyright photo was sent to foreign experts for further confirmation via email.
In August 2011, the email for the species confirmation as Macaca assamensis pelops was received from Professor Anindya Rana Sinha,  (National Institute of Advanced Studies Indian Institute of Science Campus, Bangalore 560012, India) thus adding the primate species record for Bhutan. Until then, this species was left unreported of its occurrence in Bhutan. According Dr. Sihna, it is genetically closely related to Arunachal Macaque (Macaca munzala).

Conservation status
The status of this species as per IUCN Red list is Near Threatened (NT), 2008 but the history as stated in 2004 was endangered and in 2000 was vulnerable. The population size in the wild is not known yet they are likely to be decreasing.
In Bhutan, we can assume that adequate size of population survives considering the undisturbed habitat that they use is commonly distributed. On the other hand, since they frequently raid crops, they might face the danger of retaliation killing by agitated farmers.  
In Bhutan, there are over  200 species of mammals. Bhutan has now seven primate species. Other primate species include Assamese Macaque (Macaca assamensis), Rhesus Macaque (Macaca mullata), Common Grey Langur (Semnopithecus entellus), Golden Langur (Trachypithecus geei), Capped Langur (Trachypithecus pileatus) and Slow Loris (Nycticebus bengalensis).

A joint report prepared by Mr. Rinchen Wangdi, Bumdeling Wildlife Sanctuary who is currently studying in Australia and L. Tharchen ( I have contributed minimum for this article, so credit goes to Mr. Rinchen)