Amphibian Survey & a biodiversity check-list in the Heart of Borneo, Central Kalimantan

It took three days for us to arrive in Bukit Batikap conservation forest, a local protected area as our destination for amphibian survey. We reached Bukit Batikap in the upstream of Posu River using three different modes of transportation; by air, land and water. With only two hours flight from Jakarta, we arrived at Tjilik riwut airport in Palangkaraya around 2 pm in local time, it was on Friday 28th March 2014, and it was a very unpleasant flight anyway,due to the poor weather condition with lots of air turbulence during the flight.

As we arrived in Palangkaraya, we stayed two nights in hotel for logistics and transport preparation, and to be in contact with BOSF (The Borneo Orangutan Survival Foundation). We will visit their location for the survey in Central Kalimantan, a protected forest under Murung Raya District, so then we had to prepare letters for Dinas Kehutanan and also BKSDA in order to get the expedition's paper work done.

In the third day, we left Palangkaraya around 11.00 am and heading to Tumbang Lahun, approximately  8 hours by double-cabin cars and then continued by motor-boat (called Ces locally) to Batu Ampar. We crossed several rivers, drifting in muddy road, while enjoying the fascinating view of the landscape.

Driving from Palangkaraya - Tumbang Lahun

Crossing a reddish rocky river, on the way to Camp B 

It is supposed to be a three hour trip to reach Batu Ampar from Tumbang Lahun, but due to the heavy rain last night, the river was so over flowing with water, plus logs and litters so it was really hard for the boat to move around in the river especially at night!!. We finally reached Batu Ampar at 06.00 am in the morning, instead of three hours, it took us a whole night slithering along Barito River. 
We waited around 2 hours in Ampar to prepare the transportation to Camp B using two double cabin cars; Strada and hartop. It seems impossible using ordinary cars for the trip due to the badly unpaved logging road that has been constructed and used by logging and coal mining companies.  We reached camp B in 6-7 hours from Batu ampar. 

We continued to Tumbang Naan, a nearby village close to Bukit Batikap using small boats from camp B approx. 3-4 hours. We had to stay in Tumbang Naan for a night in order to reach Bukit Batikap in the midday of the next day. We stayed in extra-ordinary home-stay, a floating home-stay we may call,running by an outsider,a guy from Palangkaraya. The house floats on the river using several big logs as buoys, located just in the side of the river. 

So, physically we still above the waving water. It was more awesome though, when we got a big fish (not really, we bought it from a local fisherman). That was a quite big fish, weighted more than 7 kg. That night we had fried and grilled fish for dinner, accompanied by lots of tiny mosquito we called agas locally, a really small and annoying mosquito that bites you without seeing it presence on your skin. 

Cloud like a ear shaped mushroom, 
the view from the floating home stay

A splendid View from the home stay in Tumbang Naan

The next day, we continued the trip to Bukit Batikap by several different boats. In local unwritten aggrements, travelers have to use local boats for their transportation in these areas. so whenever you pass a new village along the river, you have to stop and use their boats for the next of your trips. Really annoying though, you have to move your stuff several times from one boat to another, depends on how many villages you have to cross to get to your destination. 

In addition, we passed several small mining operation areas along the river. Most of them were not active, only few operation were taking place. I wonder what kind of deposits and how do they mine it, the muds or the materials along the river must contains mine deposit. Anyway, there must be the impact to the local ecosystems from this activity.

Cinnamon frog (Nyctixalus pictus)

Finally we arrived in Bukit Batikap camp in the midday of the third day. Some people from BOSF staffs already there including two volunteers from Netherlands. They are very nice, helping us settling down there and prepared for meals. After dinner, to satisfy our curiosity about the local inhabitants, we were wandering around the camp to observe what kind of animals live there, especially the frogs. We found several species of frogs just not far from the camp, in the side of the Posu River. We encountered a pearl frog Nyctixalus pictus, Microhyla  berdmoreii, Leptolalax gracilis, Rhacophorus apendiculatus and one reptil; Ahaetula Prasina. Ever since that night, we are so familiar with the calling of the cinnamon frog because we hear it singing every night. 

Bukit Batikap Conservation Forest

The entrance to Batikaf Camp, viewed from Posu River

We had a meeting last night together with all crews of BOSF. For us this was the first time, but for the rest of the people this is a daily schedule of the Batikaf Camp. This daily meeting is intended to collect all the information they have gathered related to the monitoring of Orangutan, to make a plan for tomorrow activities, and to talk about any other things if necessary. We were welcomed and introduced by the Camp manager and coordinator of monitoring to the rest of the people. There were 13 people in total at that time in the camp including two Dutch volunteers and the four of us. Everything was went smooth and we also discussed about our plan for amphibian survey in that location.

An orangutan we encountered on the way to camp

A little information about the Batikaf Camp, from the information I gathered from BOSF crews. Bukit Batikaf Conservation Forest is an insitu (if I am not mistaken) conservation program for Orangutan in Central Kalimantan, established and supported by Borneo Orangutan Survival Foundation (BOSF). This area is a place for reintroduced Orangutan, begun in to operate in 2012 and now became a home for 121 including two juveniles of orangutan. These orangutan were gathered from many places in Kalimantan, I think its been collected from unlicensed collectors or transported from oil palm plantation areas. There have been 8 times in releasing Orang utan  in Bukit Batikaf, in which 3-20 Orangutan per release. These Orangutans were placed in some pointed areas around the camp and have been monitored since. However, before they arrived in Bukit Batikaf, they have to be rehabilitated and trained in Nyaru Menteng (approx. 25 km from Palangkaraya). It was established in 1999 in order to train them how to survive in the wild (once again, with human intervention). There are 700 more orang utan in Nyaru Menteng  waiting to be released in the jungle including in Bukit Batikaf.  On 19-21 of April, 8 more orangutan have been released in Mosu river, 2 hours to the North of Posu river, we were so fortunate to be involved in the activities.

Habitat characteristic....

Bukit Batikaf area is covered by pristine forest and protected by Dinas Kehutanan (Forestry office) of Murung Raya District. The area is characterised by the lowland dipterocarpaceae forest; relatively flat which is rich in biodiversity. These include lowland dipterocarpacea birds (approximately 204 species are found here, most of them are lowland specialist according to Jhon and anna), and some mammals (approx. 6 big primates have been found here such us Pongo pigmaous wurmbi, Hylobathes muellery, Hylobathes agilis, Macaca nemstrina, macaca fasicularis, Presbytis rubicunda, Nycticebus). Other taxas such us insect and fish are quite diverse and interesting to be studied in this place. Therefore, we come here to research about the amphibians especially frogs including their ecology and habitat.

Posu River, with the characteristic of peat swamp 

forest with reddish water

A dead Microhyla berdmoreii in a pond

A big tree belongs to Dipterocarpaceae lowland forest 

We spent in the first morning in the camp by walking around, to get familiarize with the location and to prepare and install the tools we will use for the survey such as Dry-Wet thermometer. we walked around to observe the water/river condition in Posu River. The river is quite acidic perhaps due to the reddish colour of the water, a distinctive feature of peat swamp forest. It might  have consequences to the distribution of frogs in the location. In addition, during our observation, we found a dead frog (Microhyla berdmoreii) drowned in a quite reddish marshes, we were not sure about the caused of the dead, probably the water is too accidic. However, we still found some tadpoles inside the pond. 

However, the forest standing is in good condition with the high diversity of tree species and dominated by big trees such as Agathis sp and Ficus sp. in combination with many different kinds of forest dwelling. Every morning, around 5-6 am, we often hear the sound of some gibbons, the sound that probably belong to Muller's Borneon Gibbon (Hylobates Muelleri), an endemic species of Borneo Island. Birds like Meninting Cegar and White-rumped Shama or loccally known as Muray Batu, a commercial birds are found quite abundance, perching around the camp. It seems that the biodiversity in this location is stored safely, far from human disturbance.


Data collection...

Before we made transects for amphibian survey, we had already made transects on our computer using ArcGis software, a mapping tool in order to make it easier to plot the transects in the field. Actually we wanted to make as much plots as possible in three week survey (approx. 20 days). We followed the transect map we got from BOSF, since they have already put transects like a spider web for monitoring of Orangutan. By using GPS, we went to those plot we have planned earlier. 

Bukit Batikap Frog team
(from left) M. Irfansyah Lubis, Irfan, Mediansyah, and Arief Tajali

A chunk of rattan stick

We started making transects usually in the morning and will come back in the evening for frogs' observation. But, in the quite far transects, we sometime went there and making transect right after lunch so we don't have to come back to base camp, just waited there till night falls for frog's hunting. Averagely, we could make 2 transects in a day, sometime 3 transect and it only happened several times. The forest sometime hard to penetrate due to a very thick rattan forest in some places. 


Eventually, we made 15 transects during the fieldwork in almost 11 days, we did not continue making transects because the next 10 days will be used for second observation/duplication. We somehow used the available transects created by BOSF for orangutan monitoring. But in some areas, the transect already gone so we had to make new trails. Mostly our transects are located in Transect Anton (TA) and Transect Louna (TL) based on BOSF map, just to the East of the basecamp/Posu River. Some transects are located in Transect Burang-rang (TB) in the West of basecamp and TJ to the North of The Camp. 

One of our transects

We were gathering data and information about the amphibians and their habitat quality for each transect. Within 120 meters of a transect, we had to measure all habitat characteristic data such as trees and dead log's size and volume, the thickness of leaf litters, and the occurrence of water sources such as ponds,  stream, or marshes. One thing that we suppose to measure but we didn't do was to sampling the quality of  water sources. We did not bring pH meter to check the acidity of the water. It could be a good idea to sample the water as it is very important for the life circle of frogs. We observed that the water condition is quite different from one place to another, in one place is quite reddish, but it is getting more clear when it gets deeper in to the forest, quite far from the big river.

Habitat quantification

We collected frogs' information from both visual and sound encounter system from each transect. We identified them directly on site, without bring them back for further identification to the camp. Most of fogs we have discovered were common species for Borneo, although some were still unidentified species (at the moment). In addition, we also made a check list of other animals that we have encountered such as reptiles, mammals, birds, and even insects as many as possible, just for the records and report to BOSF. We got friends in the camp that helped us to identify the birds and mammals, they are Jhon and Anna, the Dutch birdwatchers who have been volunteering the monitoring of Orangutan in Bukit Batikap for two months. We also used some field guides for identification of these animals. 

Result:>> Species richness.....

The total amphibians we found is 32 species, with some are still unknown species. These includes 5 species from family of Bufonidae, 9 species from Dicroglossidae, 4 species of Megophyrdae, 6 species of Microhylidae, 5 species of Ranidae, and 8 species from family of Rhacophoridae. Leptolalax gracilis is found quite common in the forest due to very thick of leaf litters, while Megophyrs nasuta was only found several times during the survey, but it strong "Kong" sounds was heard every night. Tree frogs such as Polypedates colletti, Polypedates macrotis, Rhacophorus Pardalis and Racophorus apendiculatus were aggregated based on the occurrence of water bodies. Different type of water bodies also affected the distribution of frogs; on the fast moving stream we found Limnonectes leporinus quite common, while in marshes or small ponds were occupied by the family of Microhylidae such as Microhyla berdmoreii, Microhyla  perparva and Microhyla malang/borneensis. Interestingly, we also found some tadpoles in the tree trunk, but we could not identify the species. 

Polypedates colletti

Rhacophorus Pardalis

Megophyrs nasuta

Kalophrynus pleurostigma

The forest ground also becomes a habitat of Limnonectes finchii, one of the Bornean  frogs that has parental care by guarding their eggs in the pile of leaves, and transporting the tadpoles on its back to nearby water. We encountered one individual of this species guarding the nest. One more species that unique during this study is Rhacophorus Kajau. We found this beautiful species only one location. They lay their eggs on the back of overhanging leaves, 1-2 m above a slow moving stream. We discovered the eggs and also tadpoles of Rhacophorus kajau only in this stream, further east from basecamp. 

Limnonectes finchii, guarding her eggs

Rhacophorus kajau

As for reptiles, we found at least 33 species, these includes snakes, lizards, turtles, and soft shell turtles. Snakes from colubridae family is found quite abundance especially Calamaria sp. and Boiga sp. Cyrtodactylus malayanus inhabits mostly in the root of big trees, two individual of Cyclemys dentata are found in a quite large but slow moving stream with muddy bottom, and one juvenile of Dogania subplana is found in a more clear but small slow current stream.

Boiga nigriceps

Soft shell turtle (Dogania subplana)

In addition to our species check-list, we found at least several species of mammals which are quite easy to find such as Western Tarsier (Tarsius Bancanus), Kukang (Nycticebus sp), Muncak, and three kinds of rat which are Moon rat (Echinosorex gymnura),  Muller's rat (Sundamys muelleri) and Dark-tailed tree rat (Niniventer cremoriventer). Jhon helped us giving the species name of the mammals. The rumble sound like a thunder of a Sun bear was heard close to Transect 7 in one of our night observation.

Western tarsier (Tarsius Bancanus)

Kukang (Nycticebus sp)

During night observation, it is very common to find birds' sleeping close to a river or streams. At least we have located several of birds in this conservation forest. With a help from Jhon and Anna, we could identify the species' name of these birds. One bird we found sleeping in a hole of a dead tree, with a species name Red-Naped Trogon (Harpactes kasumba), and a sound of Brown boobook (Ninox scutulata) and a frogmouth was heard almost every night during the survey. Meninting cegar (Enicurus ruficapillus), Luntur putri (Harpactes duvaucelii), and Pauk bidadari (Pitta nympha) are found sleeping in trees close to water bodies. One day, on the way to transect 8, we encountered a pretty bird in its nest, just in the tract. I was too excited and surprised so accidentally disturbed the bird away, we found two chicks inside the nest, what a poor chicks. The bird was too stupid maybe to pick a wrong place and a wrong wood, the wood is too decay so it gets easily broken.
  

Luntur Putri/Scarlet-rumped Trogon
(Harpactes duvaucelii)

Pauk bidadari (Pitta nympha)

Two little poor chicks inside a hole of a decayed log

However, many of other species from other taxa could be found here. I believe that this forest reserves many species of wildlife, waiting to be discovered. As consequences, more biodiversity studies are needed here such as insects which we found quite diverse and unique. 

This is just a field trip report, more information of the species we found could be found in later publications, please contact the writer. 

In the end, Indonesian forest is rich in biodiversity, but not for long, soon it is gonna be a history...

Save the forest...

Save the Earth...

Save the people...

~Da Big L~