On Assignment: Batang Ai

9 October 2013

On assignment: Batang Ai

One of Sarawak’s Heart of Borneo zones, Batang Ai National Park comprises over 270 sq. km. at the headwaters of the Ai River, above the Batang Ai hydroelectric dam. This traditional homeland of the Iban people is a beautifully rugged wilderness, with undulating hills of pristine forest accessible only through a vast network of clear water rivers and streams. In addition to hosting numerous rare and protected species of wildlife, the park is home to an estimated 300-350 individuals of Borneo’s rarest subspecies of orangutan, Pongo pygmaeus pygmaeus.

Since February this year, I have made a series of expeditions into the interior of this region on assignment for Borneo Adventure, a local company that has pioneered the area’s ecotourism and worked with the Iban people to develop a sustainable conservation strategy. My work was aimed at producing images for a book showcasing the rich natural and cultural heritage of Batang Ai and the neighboring areas. After a total of six weeks in the forest, enduring torrential rains, an enormous enraged orangutan, and several destroyed cameras (including one plunging into the river with a 600mm lens, and another having its innards invaded by an army of tiny stinging ants) I tallied over 6000 captured images. Shown below is a sneak peek view of a handful of the photos. The book is scheduled for publication and release in early 2014.

Potter waspHeadhunting relicsPhrynoidis asperaFungi
River fishingAerial viewWeavingPitta granatina
Pongo pygmaeus pygmaeusChloropsis cochinchinensisNeurobasis longipesHeadwaters of Batang Ai

New Species of Gliding Frog from Borneo

18 September 2013

Few animals seem to encapsulate the magical qualities of the Bornean jungle more than gliding frogs. Armed with huge webbed feet and flaps of skin along their limbs, these colorful amphibians sport the uncanny ability to paraglide down from the tree tops and even change directions in mid-flight. Once, during a visit to the canopy walkway in Danum Valley Conservation Area in Sabah, I witnessed firsthand just how effective the gliding ability of these frogs can be. Upon arriving at a tree platform in the middle of the walkway, perhaps 50 meters above the forest floor, I noticed a small orange frog (Rhacophorus pardalis) perched on one of the wooden planks near the edge. As I approached for a closer look it abruptly leapt off the platform and I watched as it soared down through the air, carved a wide arc around a lower tree and disappeared into the forest below.

Several gliding frog species occur in Borneo, all in the genus Rhacophorus and all equally charming with their gaudy colors and oversized (seemingly ungainly) floppy feet. The most well-known is undoubtedly the large and spectacular Wallace’s Flying Frog (Rhacophorus nigropalmatus), made famous by Alfred Russel Wallace’s description and illustration in The Malay Archipelago. Smaller, but no less attractive is the Harlequin Flying Frog (Rhacophorus pardalis) which is perhaps the most common of the species, being found all across the island around muddy pools of water in the forest.

Last month a scientific paper published in Current Herpetology brought to light an entirely new species, the Bornean Gliding Frog (Rhacophorus borneensis). Perhaps the most colorful of all the Rhacophorids, R. borneensis is a pale lime-green with an orange underside and interspersed with patches of black and brilliant sky-blue. This frog had been known previously from a few scattered collections and photos from Sarawak and Sabah, but was thought to belong to the Javan Flying Frog (Rhacophours reinwardti). The new research compared both color patterns, size, and DNA, and showed that the Bornean specimens are indeed distinct from R. reinwardti, which is now believed to occur only in Java.

Rhacophorus borneensis

Like other gliders, R. borneensis is a true tree frog, and it is believed to live almost its entire adult life in the forest canopy, descending to pools of water only to breed and lay eggs. Simply judging by how rare encounters with this species are, its visits to ground level are probably even more infrequent than R. nigropalmatus or R. pardalis. The presence of R. borneensis in the forest is often only detected by the distinctive call of the male, sounding somewhat like a woodpecker drumming on a hollow tree.

So far the life-history of the Bornean Gliding Frog remains almost completely unstudied, but further research is certainly warranted for this newest member of Borneo’s magnificent gliders.


M. Matsui, T. Shimada, A. Sudin. A New Gliding frog of the Genus Rhacophorus from Borneo. Current Herpetology, August 2013; 32(2): 112-124.

The Nature of Sulawesi: Guided Tour 3-20 August 2013

17 September 2013

During our epic 3-week traverse of Sulawesi and Halmahera the group bravely faced bloodsucking leeches, overgrown trails, and several flooded rivers, but were well rewarded with some incredible sightings of rare flora & fauna. Some highlights of the trip included: close encounters with tarsiers and macaques in Tangkoko, a very rare sighting of a Lowland Anoa, and reaching the summit ridge of Gunung Lumut after several days of hiking to find the remarkable pitcher plant Nepenthes hamata.

A selection of images from the trip:

Macaca nigra nigraNepenthes hamataEurystomus azureusBabyrousa celebensis
Agalmyla sp.Gehyra marginataLitoria sp.Gunung Kiematabu
Nepenthes eymaeLitoria infrafrenata infrafrenataTodiramphus diopsXylotrupes ulysses clinias
Nepenthes glabrataBabalus depressicornisThe Nature of Sulawesi guided tour 2013Turacoena manadensis

Additional photos from the trip can be found at Rainforest Expeditions with Chien Lee on Facebook.

A new tour to Sulawesi has been scheduled for February-March 2014. Please inquire for further details.

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