Swimming with King Cobras
By Phil Oakley
During Easter 2002, I took part in an eight day caving reconnaissance expedition in Thailand. This was my third caving expedition to Thailand. With three other caving colleagues we discovered a new system in the little explored and remote Thungyai Wildlife Sanctuary.
“Snake! Get out of the water”, I shouted leaping from the river and clinging to the cave wall.
It should not have been there: They don’t normally go into caves, certainty not this far in and I was at least 100m into the cave. “You were very calm and controlled”, said Terry, a fellow team member, later that night. To me it was more of a panic reaction. When a King Cobra swims out at you in a narrow stream passage, instincts tell you to move fast. While I clung there I thought “you silly idiots” as the others stood in the water. “Well, you had the only ledge to stand on!” said Terry. They hadn’t quite understood why I was clinging to the wall otherwise we would all have been competing for the only ledge.
This was the last day, of an eight-day reconnaissance trip in the Thungyai Naresuan West Wildlife Sanctuary, Thailand. I had gone out to help Dean Smart find new caves in this relatively unexplored region. Dean works for the Royal Thai Forestry Department as their speleologist. He needed a small team of experienced expedition cavers to explore an area with great potential. Our expedition team consisted of Dean (Expedition Leader), Terry Bolger (Canberra Caving Society, Australia), Paul Johnson (Torne Valley Caving Club, England) and myself, Phil Oakley (Combined Services Caving Association, England).
The first phase of our expedition was to follow-up on a 1984 report by a Swedish caver, Bill Odell who claimed to have found 40 caves along a stretch of the Mae Klong river. The second phase was to identify possible cave resurgences in the southwestern part of the sanctuary.
Thungyai Naresuan West Wildlife Sanctuary
Entry into the Thungyai Wildlife Sanctuary is strictly controlled and limited to research purposes only. The sanctuary lies next to the border with Burma, 300km NW of Bangkok. It encompasses part of a huge karst region some 12,000km2 in size and consequently, a large proportion of the sanctuary is limestone karst. Mountain peaks rise to over 1800m and are covered predominantly in primary forestation. The sanctuary provides a home to tiger, bear, gaur, wild water buffalo, elephant and many other endangered species. A few hill tribes also live in the forest. There are problems with poaching and forest fires.
A network of ranger stations, linked by rough dirt tracks, provides the basic infrastructure in the region. During March/April the climate is hot and dry, water levels are very low and the number of mosquitoes is minimal. Normally this region of Thailand is malarial. Other dangers in the area are attacks form large animals, hence the need for armed ranger support during the expedition.
It took 7½ hours from Bangkok by bus and truck to reach the Sanctuary’s new HQ. The following day (Monday 1 April) we set off to find our first cave. After a ½ hour drive from the Sanctuary HQ followed by a two hour trek on foot through the forest we located the cave at the base of a limestone outcrop. The 10m wide entrance descended a gentle slope into a large chamber about 15m wide by 25m deep and 10m high. There was obvious evidence that locals used the cave, as Suthep – our main ranger guide - came out with cold bottled water! At the back of the chamber was a small opening into another smaller chamber with bats swooping through. The back room was blind. A rift on the left side became very narrow after about 3-4 m. The survey gave a total length of 46m. The cave was named Tham Khi Mao (Drunkard's Cave) after the guide’s corpulent drinking habit!
The following day (Tuesday 2 April) we took a 2 hour truck ride deeper into the Sanctuary to the original Wildlife Sanctuary HQ at Song Thai. From here we walked the 6 km (3hrs) down to the Nam Chon area of the Mae Khlong river where our base was to be for the next three nights. Our group consisted of Dean, Terry, Paul and myself, Suthep and four other Thai rangers. The walk was straight forward following a defined track, however the 400 C temperature and heavy packs made it hard work. We arrived at base camp and were pleasantly surprised to find a raised wooden platform with a nearby tributary river providing a water supply. We were expecting to be sleeping in the forest with no facilities.
On the first evening a quick reconnaissance of the small valley behind base camp was undertaken. A large, draughting boulder fall with a resurging river was soon discovered. After scrambling and searching among the boulders for an hour, all openings were found to quickly end and a way through to the cave behind could not be found.
Bamboo Rafting
The next day a reconnaissance of the main river was done. Initially we started along the riverbank but with steep, rocky banks covered in heavy vegetation and in temperatures of 40 o C, the going was slow and tough. After about ¾ hr of making very little headway, Terry and Dean decided to take to the river. It was not long before we were all floating down stream on bamboo poles. The river was about 30 m wide and slow flowing which made a very pleasant and relaxing way to look for caves! Three sections of small rapids were encountered which were easily negotiated by floating through them. This reconnaissance day proved fruitless for finding significant caves. None of the small tributaries marked on the map had resurgences and the rock at river level was mostly non-limestone. The few small holes that were found went nowhere. At 2km from base camp a major dry tributary (Huai Pa Chi/Huai Du Ngae) was encountered entering from the west. No evidence of a resurgence could be found.
At this 2km point we decided to start on the swim back up-stream before dark. Although enjoyable, this was not a very efficient way to explore at river level. A future expedition would benefit from using kayaks or some other small boat. However, getting boats into the area would require a lot of effort.
On Thursday we resumed our reconnaissance behind base camp. We split into two groups: Dean and myself went up a dry riverbed. We found nothing except a python. Thick vegetation and high temperatures made our progress slow and hard going. Our search ended after about 1km at the bottom of what would be a 20m waterfall during the rainy season.
Unchartered Territory
Terry and Paul returned to the boulder field from the first nights reconnaissance. They found the entrance within minutes of walking into the boulder field! After exploring a small dry upper chamber they found a way through at the back, which led to a drop of about 8m through boulders into the river passage. Containing their excitement they went about 150m upstream to see if it actually had potential and it did. We met up at base camp for a quick lunch – accompanied with a buzz of excitement. We returned to the cave and dropped into the main system at 1pm and surfacing again 8½ hours latter.
We had discovered a brand new cave system in Thailand. The active river passage was followed and averaged about 5m wide by 10m high. The rock structure was very sharp and brittle and fractured very easily. This made climbing over boulders hazardous and dangerous. On several occasions, a rock ledge fractured whilst someone was standing on it. At the first boulder fall a way over was found on the left-hand side. After 500m of large river passage, a very large boulder room was encountered approximately 80m wide by 30m high. A steep 10-20m scramble on a very loose and dangerous slope up the left-hand side ended in a hazardous 3m vertical climb before topping out. On the top of the boulders were three large standing stalagmites (approximately 5-6m high, 2m diameter) along with others that had fallen over. Loose rock and debris made scrambling across the top and climbing down the other side very hazardous.
Continuing for a further 600m the team stopped having entered the cave three hours previously. The stream passage continued on with similar dimensions. The survey showed a total of 1.1km of river passage and a gradient of 7o. The cave was called Tham Huai Tong Thai after the stream. The main sink for Huai Tong Thai is 3km from the resurgence and 225m higher in elevation. Maps suggest that other potential sinks exist up to 7km away and nearly 500m higher.
We could have pushed the new system further over the following days however, Dean wanted to reconnoitre other areas as per the expedition objective. Disappointed, we moved on but plans are underway for a return expedition in April 2003 to fully explore the system.
The next day (Friday 5 April) we walked out from Nam Chon back to Song Thai ranger station. A quick investigation of the main Huai Tong Thai sink found it to be choked. After lunch, base camp was moved to Thi Khong ranger station, a one-hour drive south from Song Thai. Along the way, one of the potential sinks for Tham Huai Tong Thai, the sink of Huai Du Ngae was briefly explored. It was choked with vegetation and debris. A small shaft also found next to the road dropped vertically for several meters but was not descended since the group did not have any vertical kit.
On Saturday 6 April we visited a known cave, about two-hour trek from the ranger station. The cave entrance was easily located with the help of the park rangers. The rangers had been into the entrance before but had not gone further than the start of a deep-water section about 50m inside. After 20m, the deep-water section turned a 90° corner and sumped. The cave was called Tham Huai Pom Phi after the local name of the stream. A dry upper level bypass ended at a 2m drop back into the deep-water section beneath. In this dry section were some interesting unidentified insects. Several leeches about 30mm long were on the cave walls. Twenty to thirty bats were present and 3-4 catfish were seen swimming in the dark, deep water. The cave fauna may prove to be interesting and further studies are needed.
King Cobra Cave
On Sunday 7 April we departed on a three-hour truck journey to the southwestern corner of the sanctuary near to Khao Laem Dam reservoir. This was to be the last area for reconnaissance. Thick smoke from numerous forest fires hung in the air obscuring the sun. On the Monday we set out on foot to an area that had been identified as having a potential cave resurgence. The walk passed local tribes and areas of farmed land. Despite this being a habitated area, nobody seemed to know of any caves or be able (or willing) to offer any kind of help. After about 2 hours a small stream was followed to the base of a 500m wide limestone ridge where a boulder chocked resurgence was found. After a scramble around the bottom of the cliff and cutting through undergrowth, an upper entrance was found. This dropped into the stream just behind the boulder choke.
I was in front, checking all the time for anything unpleasant. Initially the stream passage varied from two to three meters wide and five meters in height. After about 50 meters the passage narrowed to about one meter wide and 10 meters high. I had just emerged from a chest-deep water section and was about to go back down into water when I saw it swim towards me, less than three metres away, and closing. The others were still in the water close behind me. The young King Cobra came out about one metre and then stood its ground, head up and tasting the air. It had nowhere to go except to swim past us. The four of us stood and watched to see if it would do anything: It was a stand off.
So, that was it. We could not complete this particular cave. We backed off carefully – hoping it wouldn’t follow us - and started our survey 20m down stream. The rest of the cave is there for a future expedition group to finish! We named the cave Tham Jong Ang (King Cobra Cave) with a surveyed length of 93m. What lies beyond the King Cobra remains unknown. It certainly has the potential to go all the way through the ridge.
On the Tuesday a 4x4 truck was supposed take us to another cave about 2hrs away, but it did not arrive. Since we had to head back to Bangkok the following day, an afternoon of R & R was spent in the Burma/Thai frontier town of Sangkhlaburi. The next day (Wednesday 10 April) we returned to Bangkok which took 10hours by public bus.
Overall, this 8-day reconnaissance proved very successful. A total 1.3km of cave passage was surveyed and areas for future exploration were identified. There is the potential for a very large system at Tham Huai Tong Thai. Caves with interesting fauna were found that require further study. A return expedition is being planned for April 2003 to continue the exploration.
