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Douc Langurs (Pygathrix spp.) Fact Sheet: Population & Conservation Status

Douc Langurs (Pygathrix spp.)

Population Status

Pygathrix cinerea (gray-shanked douc langur)

  • Population trend: decreasing
  • Global population
    • Likely less than 2,000 individuals (Long et al. 2020)

Pygathrix nemaeus (red-shanked douc langur)

  • Population trend: decreasing (Coudrat et al. 2020)
  • Largest population likely in Nakai-Nam Theun National Park Area, Lao PDR (Coudrat et al. 2020)
    • At least 4,500 groups
  • Other large populations in Vietnam (Coudrat et al. 2020)

Pygathrix nigripes (black-shanked douc langur)

  • Population trend: decreasing (Duc et al. 2020)
  • Largest populations in Cambodia (Seima Biodiversity Conservation Area): 42,000 individuals total (Pollard et al. 2007; Duc et al. 2020)
  • Largest populations in Vietnam (Bu Gia Map National Park) approximately 1,800 individuals (Duc et al., in prep; Duc et al. 2020)

Conservation Status

IUCN

  • Pygathrix cinerea (grey-shanked douc langur): Critically Endangered (2015 assessment) (Long et al. 2020)
  • Pygathrix nemaeus (red-shanked douc langur): Critically Endangered (2015 assessment) (Coudrat et al. 2020)
  • Pygathrix nigripes (black-shanked douc langur): Critically Endangered (2015 assessment) (Duc et al. 2021)

CITES

  • All species listed under Appendix I (UNEP 2019)

U.S. Endangered Species Act

  • Pygathrix nemaeus: Endangered (U.S. Fish & Wildlife Service 2020)

Threats to Survival

Threats to survival (Lippold & Vu 1998)

  • Vietnam has now lost over 80% of its historical forest cover. Only 10-20% of closed tropical forest remains.
  • During the Vietnam War (1963-1975) over 72 million liters of herbicide were sprayed and approximately 22,000 sq acres of agricultural land and forests destroyed
  • Rapid human population growth. More than 70 million people in 1990 - 80% of the population practices subsistence agriculture. Remaining forests are subject to commercial logging, hunting and clearance.
  • Government policy of relocating landless northerners to central highlands is decimating forests and wildlife
  • Large-scale logging operations in most of major forests
  • Hunting for bush meat and medicinal purposes is a major activity. Many firearms in the country after years of warfare
  • Illegal trade with China
  • Subjects for taxidermy
  • Protected wildlife is for sale in markets throughout the country
  • Outside protected areas, remaining primate populations will become more fragmented

Management Actions

Conservation

  • Vietnam Government inaugurated first national park at Cuc Phuong in 1962
  • In 1986 additional national parks and reserves were established. Currently there are 87 areas totaling approximately 3% of Vietnam
  • A National Conservation Strategy was prepared in 1985. The National Plan for Environment and Sustainable Development was created in 1991.
  • At least 11 laws protect wildlife and CITES membership is in effect but law enforcement is weak, guards are underpaid, and punishments minimal (Without a set value on an endangered species it becomes impossible to set a fine for illegal hunting.)

Threats to Langurs

Red-shanked douc langur

Forest logging, hunting for bushmeat, and human population growth are causing drastic declines in douc langur populations.

Image credit: © San Diego Zoo Wildlife Alliance. All rights reserved.

Page Citations

MacKinnon and MacKinnon (1987)

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