Wednesday, June 29, 2016

[Mammalogy / Behaviour • 2016] Watering Holes: The Use of Arboreal Sources of Drinking Water by Old World Monkeys and Apes

Fig. 2. The six species displaying arboreal drinking behaviours, described in this study.
(A) Western hoolock gibbon Hoolock hoolock, (B) Northern pig-tailed macaque Macaca leonina, (C) Bonnet macaque Macaca radiata, (D) Central Himalayan langur Semnopithecus schistaceus, (E) Chimpanzee Pan troglodytes, (F) Siamang Symphalangus syndactylus, and (G) Bornean orangutan Pongo pygmaeus.

• Arboreal primates often use dipping-and-licking to drink water from tree-holes.
• Rarely reported, we describe this strategy in eight Old World primate species.
• Seasonal or habitat-specific water shortage may lead to this unusual behaviour.
• Other driving factors may be predator/human conflict avoidance or medicinal benefits.
• Effects of this strategy on population survival and health need to be explored.

Water is one of the most important components of an animal’s diet, as it is essential for life. Primates, as do most animals, procure water directly from standing or free-flowing sources such as pools, ponds and rivers, or indirectly by the ingestion of certain plant parts. The latter is frequently described as the main source of water for predominantly arboreal species. However, in addition to these, many species are known to drink water accumulated in tree-holes. This has been commonly observed in several arboreal New World primate species, but rarely reported systematically from Old World primates. Here, we report observations of this behaviour from eight great ape and Old World monkey species, namely chimpanzee, orangutan, siamang, western hoolock gibbon, northern pig-tailed macaque, bonnet macaque, rhesus macaque and the central Himalayan langur. We hypothesise three possible reasons why these primates drink water from tree-holes: (1) coping with seasonal or habitat-specific water shortages, (2) predator/human conflict avoidance, and (3) potential medicinal benefits. We also suggest some alternative hypotheses that should be tested in future studies. This behaviour is likely to be more prevalent than currently thought, and may have significant, previously unknown, influences on primate survival and health, warranting further detailed studies.

Keywords: Primate; tree-hole; dipping-and-licking; seasonal water; predator avoidance; self medication

Narayan Sharma, Michael A. Huffman, Shreejata Gupta, Himani Nautiyal, Renata Mendonça, Luca Morino and Anindya Sinha. 2016. Watering Holes: The Use of Arboreal Sources of Drinking Water by Old World Monkeys and Apes. Behavioural Processes.   DOI:  10.1016/j.beproc.2016.05.006