Chasing River Monsters!!...(From My Daily Journal in Berbak NP, Eastern Sumatra)

For people who like watching wildlife TV programmes, the River Monster is one of the best serial TV programs, especially those who like fishing and adventurous sports.This TV programme is brought by Jeremy Wide, a British television presenter and a book author. This guy travels a lot in search for the most fearsome freshwater monsters, tries to catch it and gathers information about people who were attacked by these killers.

Holding a juvenile of  salt water crocodile

So why does it matter?, well I like watching it and just recently had a field work in one of national parks in Sumatra, a peat swamp and lowland forest, located in North-eastern of Sumatra, Indonesia. This TV series and my trip has similar objective which is to save one of the rarest and endangered species of the freshwater giants from extinction and help people understand the important part of these animals for our ecosystem. In our case, the species focus is The Asian narrow-headed soft shell turtle (Chitra javanensis), one of the largest soft shell turtles in the world and endemic to Indonesia. Moreover, the information about this species is very scarce.

It was on a late summer 2014, from June-July, with a researcher from Alaska Zoo US, we headed to one of the locations in Berbak National Park, Air Hitam Laut (AHL) subsection in the Eastern coast as this site was recorded as one of the habitats of this giant soft-shell turtle. However, based on the local people we interviewed, nobody has seen this species in these locations ever. 

Unfortunately, the distribution about this species is still debated by the scientist due to infrequent  researches about it, so more studies related to it are urgently needed. However, based on limited published information about its habitat, this river giant only exist in clear-water rivers with sandy bottom which is very opposite with the condition in Air Hitam Laut  location that has very black water and muddy bottom. But, due to very limited information worldwide about its habitat, we hopefully found this endangered species or maybe other interesting animals in this kind of habitat. So we just carried out our study in this location for almost two months.

Habitat characteristics

We visited at least four different sites along AHL  river which are Simpang Malaka site, Upstream of Simpang Malaka site, the village of Air Laut Hitam, and Simpang Kubu site. The word "Simpang" itself comes from local language which means tributaries from a river.The habitat of these location are quite different from one to another. AHL  is the main channel or main river, a large size river and very deep black water. The water is so black that we could barely see like a big mirror during the day, the reflection of the the vegetation confuses our eyes sometime. The tidal influence is quite high, two to three meter in difference between low and high tide in one day, but it depends on the distance to the sea. The vegetation around the river is a bit boring though, Nypa palm or Nypa fruticans is dominated the area as it is a native species in coastline and estuarine habitat like in AHL River. 

We stayed in Berbak NP field office in Simpang Malaka, the building which is consist of two buildings, one was built by the Berbak NP, another one was built by the ZSL (Zoological Society of London). ZSL is a very active NGO in Berbak NP that working mostly on endangered species such as Sumatran Tiger. They also work for REDD or Carbon issues, together with CIFOR in building on carbon data baseline of peat-swamp forest.

On the way to Simpang Malaka Camp, A coffee like water surrounded by Nypa palms is dominated the view of the landscape

The second site is located in the upstream AHL  River, one of the branches of AHL River that local people name it Simpang Malaka. It took us 4-5 hours paddling manually using small boats to reach this location since no motor boat could reach this location due to very unpredictable water condition. This is based on several reasons, the water fluctuation is still very high and is very irreguler.  The vegetation in the sides of the stream is very thick and annoying such as Rasau (Pandanus helicopus), a thorny plant that sometime block the river. The river bottom is full of dead logs that makes hard to use motor boats to cross the river. These dead logs maybe one of the consequences from the forest fire that has been occurred several times.

This stream has been used as fishing zone as it is located and assigned by the Berbak NP authority as used zone. However, only local people that are allowed to do fishing in this place, because they have been fishing here before the national park established. There used to be many people fishing here, but since the forest fire that occurred several times, have wiped out the forest and also the fishing houses, only several people and several fishing houses that are still exist. At least, there are 9 fish houses along this river. The furthest fish house is about 3 days paddling from Simpang Malaka Camp. Rumour says that there are a lot of labi-labi or soft shell turtle in this location, the fishermen often capture them in one of their fishing gears, that was the reason why we chose this location.

One of the remaining Fish house in the upstream of Simpang Malaka River

The third location is the Village Air Hitam Laut Itself. This village has been established since long time ago, in time of insurgency that occurred in Sulawesi Island. That is why the people that live here is dominated by Bugis people, an ethnic people from South Sulawesi. There is around 2000 people live in the village, they are mostly fishermen and farmers. Over 70% are bugism, other ethnics such as Javanese! Malay, even Chinese. The farmer sometime are becoming fishermen too, they have land to farm, but still sometime go to the sea for fishing, depends on seasons though. Palm oil and coconut are the main crops here. The local people here built more parit or canals for irrigation in order to increase Palm oil and coconut production. In addition, some of the rivers are excavated to make it wider and deeper. The vegetation around the river also damaged by these activities. The local inhabitants are also raring the swift birds for their nests. It is a good commodity with high benefit. However, recently the price of the swift nests is decreased significantly, it used to be 15 million a kg, but now only 5 million a kg. The Chinese people are mostly control the economic activities in this village. They owned big coconut and palm oil farms as well as huge "Swift" bird houses and big boats for transportation and fishing activities.

A farm house between the rice field and palm oil farms and a "Swift-bird's house" are usually seen along the road to AHLVillage

The last site we visited is Simpang Kubu, the furthest and the most feared site we have stayed. Located in the heart of the park where the "King of Forest" of Sumatran Tiger rests. The site's named after a Kubu tribe, a very old and traditional tribe that used to live in Berbak Forest, approximately 50 years ago. There is no one left from this forest dwellers any more except an old lady whom were found in 1967 out of the forest, chasing by its tribe based on the local rumour. Now she lives in the AHL village, all alone and homeless. 

Similarly like Simpang Malaka stream, the forest here were destroyed by the forest fire several times. However,the quality of the forest is far better than in Simpang Malaka site. There are still a lot of big trees found standing tall such as meranti, Ramin, punak, duren, renghas, Kempas, jelutung and others. Nevertheles, Rasau vegetation is still dominated the vegetation in the river sides.

Simpang Kubu river (left) and our messy camp in Simpang Kubu (right)

We built a temporary camp for our shelter during the study in this location. We renovated an old fishing house using several small diameter of Pandanus trees as floor and plastic sheets as for the roof, we stayed for a week there. The fear of tigers from the land and crocodiles from the river has been haunting us since we stayed in this site. Anyway, we have prepared a home made cannon to keep away these wild predators.The sound of this cannon could be heard kilometres away, so loud and strong.

Survey methods

Our main objection for this research is to gather information about Chitra javanensis including morphology, distribution and its habitat preferences. We also tried to get the same data about other species of turtles and soft shell turtles. We employed trapping method in order to catch these turtles using three kinds of traps which are deep water traps, hoop traps, and Jubis (Juma and Lubis) traps. We made to almost 100 trap nights of trapping during the study, one trap night means that one trap is set down in the water per night. We have several traps used in one night, depends on location and water condition. We randomly chosen the trap locations based on our knowledge from previous studies about turtles habitat. We used boats to carry them from site to site, sometime used motor boat and sometime used paddling boat, such a hard work.

Setting the traps sometime is hard, especially when we have to deal with thorny vegetations and wild animals

Salt water crocodiles in Berbak NP

Which river monsters that live here..

As it is an estuarine area especially those that  are located in conservation areas, this place is home for salt water crocodile or Buaya Sekatak as the local people call it. We encountered several time of this ancient species during our trapping season in Berbak NP. This Crocodylus porosus is usually found basking during the day in the muddy beach in between the Nypah trees along the main channel of AHL. Their orange eyes always seen  when we flash on it using torch or headlamp at night. We even caught a juvenile of it and had a closer look at it. They seem not so aggressive like in the movies, they are easy to approach and to shoot using cameras. 

As we move further upstream of AHL tributaries and when the water salinity is decreasing, we will see more of its relative, the Senyulong or false gharial (Tomistoma schlegelii). 

Senyulong (Tomistoma schlegelii) emerges in the water at night

However, we also found one large size of senyulong basking in AHL river too. Seems like they share their habitat with salt-water crocodile. But we encountered them mostly in the further upstream rivers such as in Simpang Malaka River and Simpang Kubu River. They are very sensitive with human existence. A splash in the water from a boat could scare them away. So, it is quite difficult to approach them especially when we want to take photographs of them as evidence for their existence in this location. We sometime did night survey using boat and headlamp to see them, but still very hard to getting close to them. I got only some pictures of their eyes with very narrow snout in Simpang Kubu, they were swimming close to Bakung (water vegetation).

However, we came here not for this ancient killers, but for its far relative such as turtles and soft shell turtles. Turtles have been living for millennia, even before other land animals arrived on Earth, in time where dinosaurs dominated the Earth, based on scientific papers. What does it mean? It means that they may not the fastest animals but they are the fittest. They have been survivor this far, but now, human has been threaten their existence and lead them to extinction.

Compare to other animals on Earth such as birds, turtles are less studied. Maybe some undefined species already extinct before we know what species they are. The habitat destruction from deforestation and forest degradation is a serious threat for them. this is one of the reasons of why we eagerly doing this research, even tough its not easy tasks. Birds and mammals are easier to spot than this animal, because we could see or hear their sound. But, turtles spend all their time in the water in the wilderness.

Therefore, we are happy to find them in the wild even though we did not catch any Giant shoft shell turtles (Chitra javanensis) during the survey. We still found some of other interesting species, some of them are listed as vulnerable species and some of them even endangered species and protected under Indonesian laws. Endangered species such as Orlitia Borneensis or Kura-Kura Gading is found here, we caught them in a belat, a local fish trap. We also found a vulnerable species of Amyda cartilaginea in one of our traps. These two species together with other species such as Cuora amboinensis are very abundant here, based on fishermen information. They usually encountered them in their fish traps, and they treat these turtles as pests for the fish. There used to be some collectors came to AHL village to buy these turtles, tons of these turtles were traded before year 2000. But now, these collectors have vanished together with the decreasing amount of turtles they collect in this region.

Pak Ako, a local guide is pretending using a turtle as a pillow (left), an Orlitia Borneensis (right)

Tim Lescher with a team of local researchers holding Amyda cartilaginea

Interestingly, since the expanding of palm oil and coconut farms in the village, the canals or parit that have enormously built to enhance the production of these commodities, it may become additional habitat for some turtles such as Black Marsh Turtle (Siebenrockiella crassicollis) and Cuora amboinensis. We collected some individuals of this species during our trapping season in these parits. In addition, some villagers came to our base-camp and brought some of these turtles for us. It seems that they are very abundant in here.

Black Marsh Turtle (Siebenrockiella crassicollis)

Cuora Amboinensis

Other herpetofauna that we found abundant during the survey are Kodok Raong (Pseudobufo subasper), Kongkang Gading (Hylarana erythrea), Kongkang Kolam (Hylarana chalconota), Ular Cincin Mas (Boiga dendrophylla), Ular Karung (Acrocordus javanicus), Biawak (Varanus salvator), and Mabuya multifasciata. Kodok raong and Kongkang gading are found redundant along the river, mainly in the upstream. We came across Boiga dendrophylla several time, the last one we saw it in Simpang Kubu, it just ate two chicks as we found it lay down above a bird nest.

Mangrove snake (Boiga dendrophylla) laying down lazily after eating bird's chicks above the nest

Birds and primates diversity

I still remember that a friend of mine who works for Ministry of Forestry asked me to look for one of endemic species of birds in Berbak NP, White-hinged duck (Cairina scutulata) or locally known as Entok Rimba. This species looks very similar with common duck except it has white head. This species also becomes a symbol for Berbak NP together with Sumatran Tiger. Thus, during the survey I independently also searched for this kind bird. Unfortunately, all four locations that we have visited, I have not found this endangered species. But, other than this, we were so fortunate to see many kind of birds that live here. 

We often see and hear the unique sound of Hornbills when we cross the river as they fly from the tallest trees to another. While, woodpeckers and kipasan plays around the camp, and horror sound of night birds such as owl and frog-mouth fill the night air of the camp. One of the nights we saw a night owl hanging in a branch above the Simpang Malaka River, it was so big and beautiful, however we do not know the exact name, it could be Beluk Ketupa (Ketupa ketupu).

Beluk Ketupa (ketupa ketupu) in Berbak NP

In addition, many kind of birds live in an open disturbed areas such as in the fishing zone of Malaka River and also in Simpang Kubu River. The forest fire have changed the landscape from pristine forest to bare-land which is dominated by bushes and grasses. Such a perfect place for water birds like Cangak Merah (Ardea purpurea) and Bangau tontong (Leptoptilus javanicus) that are frequently seen in this area during our survey. Bald eagle or Elang bondol (Haliastur Indus) is soaring in the sky looking for prey such as snakes, fish, and rats.  And many others bird we saw abundance here but we do not know their exact names. 

Bangau tontong (Leptopus javanicus) in Berbak NP

Long-tailed macaque (Macaca fascicularis)

Many species of primate such as Long-tailed macaque (Macaca fascicularis), Maroon leaf monkey (Presbitys rubicunda) , Beruk or Pig-tailed macaque (Macaca namestrina), Owa Ungko, and others dwell high up in the canopy. They are mostly active calling each other when sun rises and sun sets, hanging in the top canopy of trees close to the river. The morning calls of these primates become a sign for all the living things to start a new day. And together with the swift birds that splash on the water surface in the afternoon, these monkeys' noise alert us when that day is about to end. With high curiosity, these monkeys visited us in our camps several times.

All in all, I praise the Lord that I have seen many things in this place. To see His creations is really something that could enhance my faith. However, we need to protect and conserve all these animals and their habitats in order for our grand-grand-children to see them living in wilderness.

Lets save the One and Only living planet...