Autecology of the common fishtail palm, Caryota mitis (Arecaceae), in Singapore

The only Caryota species native to Singapore, C. mitis is an important ecological resource for a diversity of fauna. However, little is known about the autecology of this charismatic, commonly cultivated palm. This is the first study that focuses on the autecology of C. mitis in Singapore, investigating the following ecological attributes: (1) their population demography; (2) differences in densities of C. mitis individuals between forest edges and interiors, and different vegetation types in secondary forests of Singapore; (3) fruit set; and (4) resource utilization for food and shelter by fauna in Singapore. Our results demonstrate that C. mitis thrives under disturbance, with significantly more individuals found in highly disturbed vegetation type, and more juveniles to adults along forest edges compared to the interior. Fruit set of C. mitis was estimated to be 31.88%, with each infructescence producing on average 805 fruits (n= 15). Eighteen species of insects over four orders (Hymenoptera; Coleoptera; Lepidoptera; and Hemiptera) were observed to utilize C. mitis for either food or shelter, and camera trapping (n = 562 trap nights) revealed five vertebrate taxa foraging on the fruits – pink-necked green pigeon (Treron vernans), oriental pied hornbill (Anthracoceros albirostris), common palm civet (Paradoxurus musangus), long-tailed macaque (Macaca fasicularis) and plantain squirrel (Calloscirurus notatus). The ecological importance of C. mitis in maintaining food resources in the highly fragmented landscape of Singapore has important implications in reforestation and rehabilitation efforts in the region, considering their potential to thrive in disturbed habitats and along forest edges.