Following the split of the silvered langurs of Indochina into two species based on molecular and phenotypic data, there is a need to reevaluate their distribution and update their conservation status. Here, we report the distribution and assess the population size of Germain’s langur (Trachypithecus germaini) within its known range across Vietnam. We confirmed this species at six of seven survey sites in different habitats within three provinces in the Mekong Delta Region, including semi-evergreen forest at the Seven Mountains of An Giang Province, mangrove forest in Ngoc Hien and Nam Can Districts and Melaleuca forest in U Minh Ha National Park of Ca Mau Province, and limestone forest at Kien Luong Karst Area and semi-evergreen and evergreen forests at Phu Quoc National Park of Kien Giang Province. We found no evidence of this species in Mui Ca Mau National Park, Ca Mau Province where it was previously reported. We conservatively estimate that the total population of Germain’s langurs in Vietnam consists of 362–406 individuals, with the largest population found in the Kien Luong Karst Area. Hunting and habitat loss are severely impacting Germain’s langur, resulting in the extirpation of the population in Mui Ca Mau National Park and small, isolated populations in the Seven Mountains and Ngoc Hien and Nam Can Districts. However, the ability of this species to inhabit a wide range of forest types, and its increasing population sizes in Phu Quoc National Park and Kien Luong Karst Area, provide signs of hope that continued conservation actions may help in its long-term survival.
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This project was funded by the Vietnam Academy of Science and Technology with the project title: “Research on current conservation status and habitat of the Indochinese silvered langur Trachypithecus germaini (Milne-Edwards 1876); propose conservation plan” (No. VAST.ĐLT.09/14-15). We would like to express our gratitude to the Southern Institute of Ecology for administrative assistance. We also thank the management board of Phu Quoc National Park, U Minh Ha National Park, and the Department of Agriculture and Rural Development of each province for permission to conduct surveys. Moreover, we also express our appreciation to the local people who contributed information to this project. Finally, we would like to express our thanks to Dr. Ramesh Boonratana and an anonymous reviewer for their valuable comments and edits.
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Van Tran, B., Nguyen, M.A., Nguyen, D.Q. et al. Current conservation status of Germain’s langur (Trachypithecus germaini) in Vietnam. Primates 58, 435–440 (2017). https://doi.org/10.1007/s10329-017-0610-2
- Population size
- Presence/absence method
- Best count