Black-crested Sumatran Langur Presbytis melalophos
image from iNaturalist
Black-crested Sumatran Langurs eat young leaves, unripe fruits, flowers (e.g. Erythrina indica, Fabaceae), mature leaves, and seeds. In Bukit Sebelah Protection Forest, much of the diet consists of leaves of Hevea brasiliensis (Euphorbiace· ae) and Ficus variegata (Moraceae), and feed mainly at 15- 20 m above the ground.
Presbytis melalophos travel along the same road and feed from the same food basically. In Kuala lumpur, they are attracted to large rare food resources. The food trees are widely spaced, and each species was highly seasonal which might indicate a larger home range. They eat mostly young leaves and reproductive parts of trees. Their favorite items were only available from any one tree species for a short time. The distribution and size of the tree they feed might influence their home range and feeding habit.
Half of their time eating foliage while half of their time eating fruits and seeds. For leaves, they are able to eat foliage from many of the common tree species which can lead to a relatively smaller home range and higher population density. They prefer those with high digestibility (relatively low levels of fiber) and high levels of protein → young leaves. For seeds and fruits, they prefer those with high concentrations of storage carbohydrates or fats, but not those rich in simple sugars.
References
[1] RA Mittermeier，AB Rylands，DE Wilson. Handbook of the Mammals of the World: v. 3 Primates[M]. Inbunden, 2013.
[2] Bennett E L. Environmental Correlates of Ranging Behaviour in the Banded Langur, Presbytis melalophos[J]. Folia Primatologica, 1986, 47(1):26-38.
[3] Davies A G, Bennett E L, Waterman P G. Food selection by two South‐east Asian colobine monkeys (Presbytis rubicunda and Presbytis melalophos) in relation to plant chemistry[J]. Biological Journal of the Linnean Society, 1988, 34(1):33-56.
