Tapanuli orangutans

Why in news?

Scientists worry that Cyclone Senyar may have killed many Tapanuli orangutans, after one carcass of the critically endangered ape was found in the floodwaters.

• Scientific name – Pongo tapanuliensis
• Family – Hominidae
• Habitat & Distribution – It is a great ape species found exclusively in the Batang Toru Ecosystem of North Sumatra, Indonesia, specifically south of Lake Toba.
• It prefers montane and hill forests, unlike other orangutans that inhabit lowland rainforests.
• Range – Their primary habitat is restricted to a small area of roughly 1,100 square kilometers.
• Population – Estimated at less than 800 individuals, making it the rarest of all great apes.

Key Features

• Discovery – Discovered as a distinct species in 2017, after genetic and morphological studies showed differences from Sumatran and Bornean orangutans.
• Evolutionary significance – It is diverged from Sumatran orangutans approx. 3.4 million years ago, and from Bornean orangutans approx. 674,000 years ago.
• Size & Weight – They are similar in size to other orangutans.
  • Females are about 1.2 m tall and weigh around 37 kg.
  • Males grow in two stages - In the first stage, they are close in size to females, in second stage, fully mature males reach about 1.5 m tall and weigh around 75 kg.
• Orangutans can live up to 60 years in the wild.
• Distinctive Features – It has thicker, frizzier fur; flanged males have a mustache and beard unlike other orangutans; cheek pads are flatter with blonde fuzz.

• Diet – Mostly fruit, but unusually includes caterpillars and conifer cones.
• Arboreal – Rarely seen on the ground, likely due to predators like Sumatran tigers.
• Reproduction – Very slow, with long mother-offspring bonds, making population recovery difficult.
• Ecological role – It act as a keystone species, vital for seed dispersal and maintaining forest biodiversity.
• Conservation Status
  • IUCN – Critically Endangered
• Threats – Deforestation, roads and mining fragmenting forests, illegal hunting and pet trade.

References

1. Down to Earth | Scientists warn Cyclone Senyar may have pushed Tapanuli orangutan closer to extinction
2. NEPC | Tapanuli orangutans