|After chasing Lion and Wild Ass , in the desert and svanna biodiversity at the western part of India, I did several explorations in different parts of country and in Africa. However, before telling stories from that part, I would like to narrate a very special biodiversity adventure of my life so far….with most intelligent apes in forest of Sumatra……my 6th exploration as a member of Exploring Nature…|
It’s a typical rain forest with insects, poisonous snakes, mud, humidity, near impossible climbs, thorny bushes, and huge canopy, beautiful and dangerous. And that’s when an explorer falls in love with the forest. Gunung Leuser National Park is one of the two remaining habitats for Sumatran orangutans (Pongo abelii). In 1971, Herman Rijksen established the Ketambe Research Station, a specially designated research area for the orangutans. Other mammals found in the park are the Sumatran elephant, Sumatran tiger, Sumatran rhinoceros, siamang, Sumatran serow, sambar deer and leopard cat. After researchers put 28 camera-traps in July 2011, 6 months later they found one male and six females and predicted the population is not more than 27 Sumatran rhinos with the total population predicted as around 200 in Sumatra and Malaysia, half of the population 15 years ago.
People living in areas with a high biodiversity value, tend to be relatively poor. Hence, the highest economic values for biodiversity are likely to be found within institutions and people living in wealthy countries. Funds can come from several sources, including bio-prospecting, the GEF and grants from international NGOs (with donations possibly being proportional to biodiversity value) (Wind and Legg, 2000).
Exploration in the forest went on by making ways through thorny bushes and crossing natural obstacles and water streams. Thankfully there was no rain last night, so the forest was less muddy than usual . There were lot of ups and downs in the hills. The 5 hours trekking in 10 km forest stretch, carrying basic first aid kits, drinking water on back and camera in one hand, was a bit tiring specially in humid conditions.
The Sumatran Lowland Rain Forests are one of the most diverse forests on Earth and also one of the most threatened. These forests contain comparable levels of species diversity like the richest forests in Borneo and New Guinea. The Sumatra rain forests are home to some of the world’s most charismatic flowering plants: Rafflesia arnoldii, which produces the largest flower in the world (up to 1 m wide), and Amorphophallus titanum, which stands more than 2 m tall and produces aroid flowers. The avifauna is also exceptionally rich. More than 450 bird species are found here, more than in any other ecoregion in the Sunda Shelf and Philippines bioregion, except the Borneo Lowland Rain Forests. In the past fifteen years, rampant logging, hunting, fires, and habitat loss in the lowlands have pushed many of this ecoregion’s already endangered species to the edge of extinction. These include the Sumatran rhinoceros, Malayan tapir, tiger, Asian elephant, and orangutan. Illegal logging and pervasive corruption are contributing to more than 3,000 km2 of forest lost every year in this ecoregion. At the current rate, no mappable natural forests will remain beyond 2025.
Sumatra’s rain forests are quite diverse and contain levels of species diversity comparable to those of the richest forests in Borneo and New Guinea and are much richer than Java, Sulawesi, and other islands in the Indonesian Archipelago. Large, buttressed trees dominated by the Dipterocarpaceae family characterize Sumatra’s lowland rain forests. Woody climbers and epiphytes are also abundant (Whitten et al. 2000). The lowland rain forests of Sumatra support 111 dipterocarp species, including 6 endemics. The emergent trees, which can reach 70 m tall, are also dipterocarps (Dipterocarpus spp., Parashorea spp., Shorea spp., Dryobalanops spp.) and, to a lesser extent, species in the Caesalpiniaceae family (Koompasia spp., Sindora spp., and Dialium spp.). Dipterocarps dominate the canopy layer as well. Other canopy and understory tree families those are common, include Burseraceae, Sapotaceae, Euphorbiacae, Rubiaceae, Annonaceae, Lauraceae, and Myristicaceae (Whitten et al. 2000). Ground vegetation usually is sparse-mainly small trees and saplings of canopy species, herbs are uncommon.
Figs (Moraceae) are also common in the lowland rain forest. There are more than 100 fig species in Sumatra, and each species is usually pollinated exclusively by a single fig-wasp (Agaonidae) species. Figs may produce (mast) from 500 to a million fruits twice a year and are important food sources for many forest animals (MacKinnon 1986). Dipterocarps also use mast fruiting, perhaps to escape seed predation, by satiating the appetites of seed-predators and leaving the remaining seeds to germinate (Whitten et al. 2000). Sumatra once contained pure stands of rot- and insect-resisting ironwood (Eusideroxylon zwageri) forests. Ironwood is a member of the laurel family and is distributed throughout southern Sumatra, Kalimantan, and the Philippines. Ironwood forests are dominated by Eusideroxylon zwageri but may have also contained Shorea, Koompasia, or Intsia species as emergents (Whitten et al. 2000).
Me and my guide Eno were making their ways through this rain forest vegetation and I was pausing intermittently to take photos. After an hour of trekking, Eno stopped suddenly and whispered, “Basu, careful”, his eyes were fixed on the branch of a fig tree. He spotted a green temple viper. Tropidolaemus wagleri is a venomous pit viper species native to Southeast Asia. No subspecies is currently recognized. It is sometimes referred to as the temple viper, because of its abundance around the Temple of the Azure Cloud in Malaysia. This snake, that usually can be found hanging from the trees, has pretty dangerous bite and in case you are bitten, you should be acting rapidly. The area that is bitten, must be immobilized with the stretch bandage and the victim should be transferred to an emergency room to be observed.
Anyway, the snake was not moving from its place and we moved rapidly to other side of the forest.
After another 15 minutes of walking, Eno asked me to stop again, both of us heard sounds of moving tree branches, as if something heavy was shaking the trees at the top. We looked up and saw something which never could be forgotten in whole life.
It was the largest arboreal mammal of this planet, closest primate to human being, which shared 97% of DNA symmetry, one of the last few of them, a Sumatran orangutan.
As of 2015, the Sumatran orangutan species has approximately 7000 remaining members in its population, only. Meena was one of them and considered most aggressive. But the one the explorer spotted was not her, but her sister Flat Nose and her baby.
“It is good that she is not Meena”, whispered Eno. He was attacked once badly by her and showed the wound on his hand to explorer.
Flat nose and her baby stopped, they spotted people in forest. Climbed down a bit to get a closer look and then started moving again from one tree to another tree by displaying amazing acrobatic skill. Orangutan has typical way of doing it, they first bend the branch of trees which they hold, by their body weight and then reach to the next branch and moved from the previous one to the next one. Skill fully maintains body balance while doing so. Kids follow the exactly same route what their mother shows. If their mother climb down from one tree and climb up the next one, instead of jumping, the kids will do same without even understanding reasons behind it.
We kept following them for next 15 minutes and reached to a part of forest where they joined few more female and cubs.
……. To be continued !!