IAS Gyan

Daily News Analysis


6th September, 2023 Environment

Disclaimer: Copyright infringement not intended.


  • The Delhi Zoo now houses a new animal species – the stump-tailed macaque.



  • The stump-tailed macaque, also called the bear macaque, is a species of macaque native to South Asia and Southeast Asia.


  • It is distributed from northeastern India and southern China into the northwest tip of West Malaysia on the Malay Peninsula.
  • It is also found in Burma, Thailand, Laos, Cambodia and Vietnam.

Range in India

  • In India, it occurs south of the Brahmaputra River, in the northeastern part of the country.
  • Its range in India extends from Assam and Meghalaya to eastern Arunachal Pradesh, Nagaland, Manipur, Mizoram and Tripura.


  • The stump-tailed macaque has long, thick, dark brown fur covering its body, but its face and its short tail.
  • Infants are born white and darken as they mature.
  • As they age, their bright pink or red faces darken to brown or nearly black and lose most of their hair.
  • Males are larger than females a trait known as sexual dimorphism.
  • Males measure between 20 and 26 in (52-65 cm) tall and weigh between 22 and 27 lb (10-12.2 kg).
  • Females are typically between 19 and 23 in (48-58 cm) and weigh around 16.5-20 lb (7.5-9 kg).
  • Stump-tailed macaques may live up to 30 years, but their lifespan in the wild is often shorter due to stressors such as predation.
  • Like all macaques, this species has cheek pouches to store food for short periods of time.


  • It is generally found in evergreen tropical and subtropical moist broadleaf forests, at different elevations depending on the amount of rainfall in the area.
  • It depends on rainforests for food and shelter and is not found in dry forests except where it ranges in the Himalayan region of India.
  • With its thick fur, the stump-tailed macaque can live in cold climates at elevations up to 4,000 m.

Behavior and Lifestyle

  • Stump-tailed macaques are semi-terrestrial primates.
  • Their large body size and weight make them clumsy climbers so they spend most of their time on the ground.
  • They forage, travel, rest, and groom on the ground, although they are known to occasionally climb trees in search of delicious fruits and to sleep at night.
  • In general, adult males are found in trees more often than other troop members.
  • They climb up to protect and watch over their groups, alerting them to any potential dangers.


  • It is primarily frugivorous, but eats many types of vegetation, such as seeds, leaves and roots, but also hunts freshwater crabs, frogs, bird eggs and insects

Group Dynamics

  • They live in multi-male, multi-female social groups made up of several monkey families.
  • The total number of individuals in any one group can vary from just a few monkeys to up to 60.
  • Males, upon reaching sexual maturity, leave their family group and social group to join a new group.
  • Females remain within the social groups they were born into for the entirety of their lives.

Ecological Role

  • ​As frugivores, stump-tailed macaques eat fruits and deposit their seeds throughout their habitat.
  • This makes them important seed dispersers within their environment—without these monkeys, forest plant growth and regeneration would be impacted.

Conservation Status

  • The stump-tailed macaque is classified as Vulnerable by the International Union for Conservation of Nature (IUCN, 2015), appearing on the IUCN Red List of Threatened Species.


  • Populations are projected to decline over the next 30 years due to threats such as hunting and habitat loss. As human populations and their demand for land increase, primate habitat is often destroyed, fragmented, or degraded so that the land can be utilized by people.
  • For example, in India, land clearing for agriculture reduces stump-tailed macaque habitat and increases the chances of human-macaque conflict.
  • Increasing interactions with humans leads to increased hunting, as the large-bodied macaques are viewed as a significant and easily attainable source of protein.
  • Certain regional populations of stump-tailed macaques are more threatened than others and at greater risk of extinction.
  • Stump-tailed macaques living in India are at high risk of local extinction due to hunting and habitat loss, while populations in China, Myanmar, Vietnam, Laos, and Cambodia are declining. Populations in Thailand are more stable.

Conservation Efforts

  • While conservation challenges to stump-tailed macaques are many, so too are conservation efforts working to ensure this species’ continued existence.
  • Protected areas aimed to preserve macaque habitat provide these monkeys with space safe from human encroachment. Protected areas throughout the macaques’ range, such as Balpakram National Park, Mehao Wildlife Sanctuary, Murlen National Park, and Huay Kha Khaeng Wildlife Sanctuary are all known to provide protection to stump-tailed macaques.
  • The establishment of more protected areas throughout their range would offer further protection.
  • Stump-tailed macaques are protected under the Convention on International Trade in Endangered Species (CITES) Appendix II, which places strict regulations on the trade of stump-tailed macaques and aims to control the number of these animals that are hunted.
  • They are also under wildlife protection acts in India, Vietnam, Myanmar, and Laos, although macaque hunting and trading continue.


Q. Consider the following statements with reference to Stump-Tailed Macaque.

1.    This species has cheek pouches to store food for short periods of time.

2.    They exhibit sexual dimorphism.

3.    In India, it exclusively occurs in the Himalayan region.

4.    The stump-tailed macaque is classified as Critically Endangered in IUCN Red List of Threatened Species.

How many of the above statements are incorrect?

A) Only 1

B) Only 2

C) Only 3

D) All

Answer: B) Only 2 [Statements 3 and 4 are incorrect]