January 2006 — Rambutans Attract Monkeys

BY ANGELA HIJJAS

Greetings to all for Christmas and the New Year. Our rambutan trees are in fruit and are just the right colour for the season. We have had plenty monkeys around to enjoy the fruit, and interestingly, if not surprising, is the fact that the long tailed macaques eat the fruit weeks before it is ripe, therefore securing an evolutionary advantage over humans who must wait, and most likely miss out. But apparently rambutans are adapted to this predation as well, as I noticed as I weeded lots of quite mature seedlings this morning: they obviously germinate from immature fruit. The fruit is green, but the seed is viable.

As well as the ubiquitous macaques, we have what I thought is the Banded Langur. However I’m not clear on the species differentiation, as this one was photographed on 17th December fits the description of the Dusky Langur. It could be that we have both species visiting occasionally.

Dusky Langur, Trachypithecus obscurus, TL 110 – 115 cm.

Most individuals are dark grey, with paler grey on hindlegs and crown and a pale grey or whitish belly patch, sharply demarcated from darker back. The bare skin on the face is dark grey with bold white interrupted rings around the eyes and a white patch over the mouth. Newborn young are bright golden-yellow, like other Trachypethecus. Call is a loud, double snort or grunt, rendered as ‘chengkong’ in Malay. Occurs in a wide range of habitats from montane to coastal forests including some offshore islands. Feed mainly on leaves, nuts and fruits. In peninsular Malaysia, tends to feed higher and in larger trees than Banded langur, Presbytis femoralis, when both species occur together. Found in troops of about 15 individuals with a single male. Gives birth to a single young after a gestation period of about five months. Range includes southern Myanmar and Thailand, peninsular Malaysia and some adjacent islands.

Photographic Guide to Mammals of South-East Asia, by Charles M. Francis