The 2002 IUCN Red List puts Borneo orangutans in the category of an endangered species while Sumatran orangutans are categorized as being a critically endangered species.
More than 80 orangutan experts and observers from all over the world gathered in Jakarta in January 2004 to attend the International Workshop on Population Habitat Viability Analysis (PHVA), in which the latest potential population of orangutans in Borneo and Sumatra and the factors influencing the survival of these species were analyzed.
According to an estimate made in 2004 by PHVA, the population of Sumatran orangutans of the Pongo abelii species stands at 7,501, spread in 13 habitats.
Meanwhile, Borneo orangutans have three subspecies, namely Pongo pygmaeus pygmaeus in the northwest of Borneo, starting from the northern part of Kapuas up to Sarawak, Pongo pygmaeus wurmbii in Central Borneo, starting from the southern part of the Kapuas up to the western part of Barito, and Pongo pygmaeus morio in the northeast of Borneo, namely in Sabah and East Kalimantan.
The total population of Borneo orangutans is estimated to stand at 57,797, therefore bringing the total population of orangutans in Borneo and Sumatra to 65,298.
From The Jakarta Post. Nov. 22nd, 2005