ORANGUTANS are featured as Borneo’s symbolic image in tourist brochures worldwide for itineraries to Sabah, Sarawak, Brunei, Kalimantan and Sumatra. I just wonder how much longer these apes, the most intelligent of all primates, will be allowed to live, undisturbed, in their natural habitats. They like us, in order to find food for our families, may well adapt to urban environments in search of survival. Certainly, ‘push’ and ‘pull’ factors may enter their lives as much as they have in human migrations from rural to urban environments.
The word orangutan first entered the English language in 1699. I first met the wild nature of a male orangutan at Sepilok Orangutan Rehabilitation Centre, in Sabah, in 1998. Like other visitors, I was awaiting feeding time for these great apes but spotted a large male orangutan sitting alone in a tall tree. When the keepers brought food to a feeding platform, he shot down the tree, swept me aside with one of his swinging arms, snatched two combs of bananas from the feeding platform and disappeared into the rainforest.
My next encounter with these apes was a few days later on the Kinabatangan River and again at Danum Valley to witness them acrobatically swinging through the primary forest and building their intricately woven nests before nightfall. On a visit to Semenggoh Nature Reserve near Kuching, an orangutan affectionately touched the hand of an unsuspecting American, then quietly and gently reached around the woman’s back with its other long arm to open the top of her backpack and remove the lady’s lunch! The latter confirmed researchers’ findings that these great apes are the most intelligent and creative of all primate species.
Earlier species, now extinct, once roamed in drier environments in southern China, India, Pakistan, Thailand and Vietnam between 12 million and 100,000 years ago. The Bornean species date back 400,000 years, walking here over the dry sea beds during the Pleistocene Ice Ages when the sea-levels were much lower. Until last November, it was thought that only two species of orangutan existed: the Bornean (Pongo pygmaeus) and the Sumatran (Pongo abelii). Researchers have discovered a third species (Pongo tapanuliensis) found, in small numbers, just south of Lake Toba in northern Sumatra. This species, through DNA testing, is more related to the Bornean than the Sumatran species! Within Borneo island, there are three subspecies identified to date; in northwest Sabah, to the east of Sabah and Kalimantan, and in southwest Sarawak and Kalimantan.
Habitats and habits
Just surviving today in primary and secondary dipterocarp and peat swamp rainforests and spending most of their lives in high trees, the Sumatran species lives at altitudes as high as 1,500 metres, but no Bornean species is found above 1,000 metres above sea level. Preferring fruit with fatty and sugary pulp, such as figs, they very much like lowland forest for its abundance of plentiful, fresh fruit, devouring over 300 different types of food together with insects, honey and even birds’ eggs. Occasionally they seem to have a passion for eating small stones and soils with a high clay content. It is thought that ingested clay absorbs toxins and is a cure for diarrhoea, or even provides a mineral supplement.
The freedom of movement of the swinging of orangutans from branch to branch is facilitated by their four fingers and a long thumb, similarly represented in their toes. These digits can grasp very firmly on branches or very gently when stroking each other. Their main joints, unlike ours, offer far greater elasticity, for they are the true ‘swingers’ of the forest.
Feeding for up to three hours each morning, it is not surprising that they take a lunchtime siesta and then move around in the afternoon, even onto the forest floor where they walk on their fists. As dusk begins to set in, they quickly and efficiently prepare their nests by tugging and bending branches together to create a central point, not unlike an upturned tepee. Smaller leaf-bearing branches are then woven in slat-like fashion and a blanket of leaves is added to cover their bodies. Natural meteorologists, they can sense impending rainfall and adapt accordingly by constructing a roof over their nests.
Stages of life
Male orangutans reach ‘manhood’ at 15 years, whereas females take six to 11 years to reach ovulation with a menstrual cycle and a gestation period not dissimilar from humans. Females give birth to their first child at about 15 years of age, before the next birth occurs eight years later. Not unlike human males of yesteryear, the father plays little part in the rearing of their offspring and the mother is left to the rearing and education of the young about social and survival matters. Eventually the baby is weaned after four years. A newly-born orangutan can live for 30 years or more. Captive orangutans in zoos can live up to 40 years of age.
In both Malaysia and Indonesia, orangutans are rightly classified as protected species and on the International Union for Conservation of Nature (IUCN) Red List, they are seen as Critically Endangered. Policing remote forest areas is indeed difficult. That said, recently the Indonesian police arrested a gang of four men and a 13-year-old, who inflicted 130 gunshot wounds and 19 machete cuts in their kill of an orangutan. This ape had been munching oil palm and pineapple fruit in a plantation. For their illegal acts, each man will face up to five years in prison and a maximum US$7,400 fine.
It is inevitable that when orangutans’ natural habitats are destroyed for mining, logging, palm oil, and road construction, they will migrate to new pastures and often raid villagers’ vegetable plots. Hunting for their meat and/or the snatching of baby orangutans from their shot mothers to supply the illegal pet trade has cost the orangutan population so very many lives.
Last February, The Max Planck Institute of Evolutionary Anthropology and the German Centre for Integrative Biodiversity Research, Leipzig, together with Liverpool John Moores University, UK, produced a joint paper, based on extensive research, which recorded that between 1999 and 2015, the total number of orangutans in Borneo was reduced by more than 100,000 animals!
This research revealed that orangutans are more resilient to change than was formerly thought and can now be found feeding on oil palm and acacia. Their estimated population numbers read as follows: 1,100 in Sabah, 4,800 in East Kalimantan, 31,500 in Central Kalimantan, and 7,425 in Sarawak and West Kalimantan.
Some of these populations are relatively stable but because they are a slow breeding species, Prof Serge Wich, a worldwide authority on these primates and one of the joint authors of the report, has stated, “If only one in 100 adult orangutans is removed each year from populations in Borneo, this population has a high likelihood of becoming extinct.”
It is reassuring, however, that Malaysia, Brunei and Indonesia are all taking effective measures with environmental impact assessments for the protection of these animals. It is only through education in remote rural areas and public awareness of these illegal killings and of the kidnapping of baby orangutans for the black market pet trade that such matters will be properly addressed.
We need to report any sightings of these illegalities to the police. We should take heart in the knowledge that long-term action plans for the preservation of orangutans in Malaysia and Indonesia are well under way. Without these in place, the tourist industry could well take a downturn. We need to be realistic, for there are thousands of tourist spots worldwide that offer beautiful beaches, friendly people of different cultures, coral reefs, rain forest experiences, river excursions and local food, but only Borneo can extend this list, to include, ‘The land of the orangutans and hornbills’.
Please support all orangutan sanctuaries in both Sabah (Sepilok) and Sarawak (Semenggoh and Matang Wildlife Centre), for public donations are necessary for their superb work in the rehabilitation of rescued primates. Otherwise our nearest relatives in the animal kingdom will see the further demise of these extraordinary primates.