The usual suspects... A female leopard cat and her kitten, photographed close to  the border with an oil palm plantation.  Leopard cats were the only species of   wild cat recorded in this forest.

Rather worryingly our camera trap survey of the Kabili-Sepliok Forest Reserve has failed to detect the Sunda clouded leopard.  Is this a true reflection of the localised extinction of these felids in this small and relatively isolated forest block or simply our failure to detect what is actually there?

 

Camera trapping is undoubtedly a powerful research tool and can quickly produce indisputable evidence of a species’ presence in an area. Proving beyond doubt the absence of a species, however, is a rather more difficult affair, and the lack of any camera trap images obtained during a survey does not necessarily prove its absence.  This is particularly true of difficult to detect species such as clouded leopards.

Stray dogs were found at multiple sites across the whole of the forest.  Could their presence be one causal factor in the absence of clouded leopards?

Nevertheless, this was a relatively intensive survey involving a high density of 35 paired cameras sites coupled with an additional 14 sites at which video camera traps were operational. This effort resulted in over 39,000 images and video sequences, including the similarly difficult to detect sun bear. Given this effort, in my opinion, we probably would have detected clouded leopard had they been present, and thus I am strongly inclined to conclude that they are no longer found in Sepliok.  That is not to say that there are not any transient individuals moving through the area from time to time, but it seems unlikely to me that there is a resident population of animals living there.

Although unwelcome news, this is not altogether surprising given the fact that the forests in Sepliok have been reduced to about the size of a single clouded leopard’s home range – ca 40 km2.  Although unwelcome, this finding is another piece in the puzzle to understand what factors control the distribution of this felid on Borneo.

Whilst it's not great news for Sepliok's Sunda clouded leopards, a number of Bornean carnivores were detected in this forest, including leopard cats, sun bears, common and banded palm civets, and yellow throated martens (see video sequence above). Potential prey species including mouse deer, yellow muntjac, sambar deer and bearded pigs were present in apparently good numbers.

Our team will now conduct an extensive questionnaire survey of the Sabah Wildlife and Forestry Department officers working in this area, in an attempt to determine when this species was reliably last seen.  Meanwhile, we have recently moved our camera traps to an area of oil palm plantation immediately to the west of Sepilok, to investigate what species are using this highly modified habitat.

Our team cannot be accused of hanging around.  Having unloaded the last of our gear from the Danau Girang Field Centre’s boat to our trusty truck, we waved goodbye to the mighty Kinabatangan river and set off in search of our next survey site: The Kabili-Sepilok Forest Reserve. 

The Kabili-Sepilok Forest Reserve and the adjacent Sepilok Forest Reserve (typically collectively referred to as Sepilok) is an incredibly interesting forest. Home to the world famous Sepilok Orang Utan Rehabilitation Centre, and just a stone’s throw from Sabah’s second largest city, Sandakan, it is home to a diverse array of forest formations and wildlife. Hill Dipterocarp, riverine, Kerangas (heath), and mangrove forests all jostle for space in this relatively small (km²) and isolated forest fragment.  And therein lies the potential problem for its felid inhabitants. Surrounding this matrix of forest, and forming the northern, eastern and western borders, is an assortment  of anthropogenically modified habitats, predominated by oil palm, but also including orchards, industrial areas and housing (see below).  Beyond the mangroves to the south lies the Sepilok Sea, and in the far south west corner a narrow corridor of mangrove links the Sepilok fragment to an extensive area of mangrove that reaches, albeit broken in places, to the mouth of the lower Kinabatangan.

Does this mangrove constitute a corridor connecting wild felid populations between Sepilok and the Kinabatangan, and if not, is Sepilok large enough to support viable populations of clouded leopards and other felids?  What species of wild cat still persist here? Over the next few months we will attempt to shed light on these important questions.  Wish us luck!