JAKARTA – The orangutan population on the Indonesian island of Borneo experienced a sharp decline between 1999-2015 due to poaching, deforestation and industrial plantations, according to a study published by science magazine Current Biology.
The growing demand for natural resources has killed more than 100,000 orangutans, according to the research which was published late on Thursday, carried out by Maria Voigt, Serge A Wich and Marc Ancrenaz.
The study says that clearing of forests for plantations was the main culprit behind the steep losses in the orangutan population, although logging and poaching have also caused a large number of deaths.
At least 2,256 orangutans have died every year on average between 1999-2015, due to poaching and conflict with humans in Kalimantan, the Indonesian part of Borneo which covers most of the island.
The three main orangutan metapopulations – a group of populations of a species separated by space but interacting with each other – of the orangutans in Kalimantan are in western Schwaner, eastern Schwaner and Karantan.
During the research period, western Schwaner lost 42,700 orangutans and was left with 40,700, eastern Schwaner lost 20,100 to remain with 16,800 and Karantan lost 8,200 and was left with 9,000, according to the estimates.
The study predicts that between 2020-2050, the animal’s numbers in western Schwaner, eastern Schwaner and Karantan will be reduced to 31,500, 14,700 and 6,100, respectively.
“Only 38 out of 64 identified metapopulations retained more than 100 individuals,” researchers said.
According to the study, political will and social participation could still secure a future for orangutans in Borneo and suggests measures such as educating people, collaborating with logging or paper companies and plantations, and plans for sustainability in land use and exploitation of natural resources.
In August 2017, the government published the Population and Habitat Viability Analysis for orangutans, which said there were 57,350 orangutans on the Borneo island.
The International Union for Conservation of Nature classifies the species as critically endangered.
The flora and fauna of Borneo has suffered severe damage in the recent decades due to the expansion of plantations of palm and rubber and forestry serving as raw material for the paper industry.