AS-HOPE report

Number: AS-23-020-2

Effects of Environmental Factors on Evolution of Social System in Proboscis Monkeys

Report: Matsuda Ikki

Date: 2011/9/15 - 2011/11/15

To assess the effects of environmental factors, e. g. , food availability and predation pressure, on the evolution of social system in proboscis monkeys, I conducted the filed survey collaborating with the Sabah Wildlife Department and University Malaysia Sabah. I collected the behavioral data of proboscis monkeys in the riverine forests along the Menanggul River in Sabah, Malaysia. In addition to the behavioral observations, I conducted the phenological survey to estimate the food availability of proboscis monkeys inhabiting the riverine forest. I also conducted the preliminary survey in the mangrove forest where is usually swampy and difficult to follow the monkeys in inland. I attempted setting up the vegetation plots in the mangrove forest to compare the food availabilities between riverine and mangrove forests. Finally, I visited the Sabah Wildlife Department and the Institute for Tropical Biology and Conservation, University Malaysia Sabah and discussed findings from this research with Malaysian collaborators. 

Inside the mangrove forest


Preliminary survey in the mangrove forest

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