Khao Sok National Park
About Khao Sok
At 160,000 acres, it is one of the larger parks in Thailand and with its spectacular lake and limestone cliffs, one of the most popular for nature lovers. There are now about 60 accommodations, from resorts and guesthouses to hostels and bungalows operating in the vicinity of Khao Sok National Park. One of the oldest and most picturesquely located resorts is Our Jungle House.
An oasis of nature surrounded by rubber and palm oil plantations, the park is divided into two parts. The first area is around park headquarters, reachable by vehicle on a well paved road passing a small village of shops, guest houses, and local restaurants. The second area is Cheow Lan Lake. A 45-minute drive from Khao Sok village, Cheow Lan Lake is known for its stunning vistas, floating raft houses, and inviting waters.
50,000 – 37,000 years ago
There is evidence of human habitation on Borneo between 37,000 and 50,000 years ago. The last ice age ended about 10,000 years ago, meaning there could have been migrations (by land) from Borneo to Thailand during the period of the ice age. There is also biological evidence, for example, the bamboo species Gigantochloa balui is usually found in cultivated areas of Borneo – never truly wild, yet this species has been discovered growing wild on the Thai peninsula. It is highly unlikely this species moved between these countries without being transported by human beings.
2,500-1,300 years ago
Archaeological evidence has shown that the “Southern Silk Road” from the Greek and Roman empires to China went overland across the isthmus of Thailand in ancient times. Instead of sailing around the Malaysian peninsula, traders would haul their goods overland between the Andaman Sea and the Gulf of Siam. Huge amounts of beads have been found, along with ancient foreign artefacts like Persian pottery, Chinese porcelain, and coins and stone inscriptions from India.
Nearby, Thung Tuk on the Andaman coast emerged as a major trading station around 150 AD, and was a market for spices, tin, and goods from China, India, the Middle East and the West. Ancient artefacts have been found all around Khao Sok, including Kapoe to the West and Phunpin to the East, where archaeological digs have revealed giant Bhodhisattava statues, ceramic Buddha amulets, and silver Arab coins dating to 767AD.
The first accounts of people living in Khao Sok date back to the reign of King Rama II, when the Burmese attacked south western coastal towns and many local people fled into the jungle for safety. As news spread that the region was rich in animal life, with fertile alluvial soils and good rainfall, more people came to the region.
A deadly epidemic swept through the region killing a large number of the population, those who survived moved out of the area. The village became known as “Ban Sop” – which means “Village of the Dead”, although there is a mountain in the local area known as “Khao Sop” or “Corpse Mountain” which may also be the reason the village was named this way.
The 401 road was constructed between Phun Pin on the east coast and Takuapa on the west coast. This opened up the whole area for settlements and plantations, modern weapons and tools that came with the new settlers meant nature was in trouble. The logging, tungsten and tin mining industry soon followed, at the expense of the forest and the Sok river, which turned brown with sediment.
Thai student activists, labeled as communist insurgents by the government, set up a stronghold in Khao Sok, since it was ideal territory to hide and operate guerrilla warfare. Between 1975 and 1982 these students not only kept the Thai Army at bay, but also kept the loggers, miners and hunters out. Had it not been for this seven year occupation, Khao Sok’s forests may well have gone the same way as much of the rest of Thailand’s wilderness – up in smoke.
22nd December 1980
Khao Sok National Park was established. Also during this period there was considerable interest from the government and the Electricity Generating Authority of Thailand (EGAT), since research had shown Khao Sok to be the largest watershed in southern Thailand.
EGAT established the Ratchaprapha Dam – creating a 165-square kilometre lake inside the National Park – to guarantee a source of electricity to the south, which by now had become a major holiday destination.
*Remarkably, thanks to the communist insurgency, Khao Sok National Park boasts one of the largest tracts of remaining virgin jungle in Thailand today. Read the fascinating account in a blog (include link to the blog) by Dick Sandler, founder of Our Jungle House.
Cheow Lan Lake is a wonderland of towering limestone cliffs and primordial wilderness. Over 100 islands dot the lake, often rising to spectacular heights from the surface of the lake. Amidst the cliffs and islands, the twin peaks of Khao Serow dominate the skyline at nearly 1,000 meters. The lake is surrounded by the virgin rainforest of Khao Sok National Park – giving you direct views into the canopy where you can see rare animals with greater ease than anywhere else in Thailand.
History of Cheow Lan Lake
About an hour’s drive away from National Park Headquarters lies the Ratchaprapha Dam, which means ‘Light of the Kingdom,’ a fitting name for a dam built to provide electricity for the rapidly developing area. In 1982, the government of Thailand began construction of the 94-meter dam on Klong Saeng, the largest river in Southern Thailand.
At the time, the area was still a hideout for political activists who had fled Bangkok during the military crackdowns of the 1970s. By 1989, the rebels had been granted amnesty, and the reservoir had filled up to create the 165-sqkm Cheow Lan Lake. The area submerged by the dam was historically used for fruit farming and as a trade route between the Gulf of Thailand and the Andaman Sea. Nowadays, the lake is utilized by fishermen, day trippers, and floating bungalows.
Watching the cliffs from the water, it is common to see gibbons, several species of monkey, and other canopy dwelling creatures that are not often seen from the forest floor. In fact, some animals have adapted specifically to the lake’s karst ecosystem. Instead of nesting in tree hollows, Great Hornbills conceal their young in small alcoves on the cliffs, which they cover with branches, leaving only a small hole to deliver fruit.
The further north you go on the lake, the more wildlife you will find grazing at the banks – elephants, gaur, deer, and tapir. Hiking through the jungle, the experienced rangers and guides often spot animal tracks and the occasional wild cat.
While the open spaces take the spotlight, the dark caverns that line the lake are as fascinating. During the dry season, you can hike to Nam Talu and see its cave river ecosystem teeming with interesting wildlife such as cave crickets, glowworms, bats, and the occasional cave shrimp. Visitors seeking an easier excursion can take bamboo rafts out to the Coral Cave and marvel at its riveting and peculiar rock formations.
Attractions and Accommodations
All journeys at Cheow Lan Lake start at the Rajaprabha pier, lined with longtail boats used for fishing or exploring the many secluded coves and islands. Day trips feature a stop at the floating raft houses, and for overnight trips, you can stay in bungalows made from natural materials. The rooms are basic but comfortable, and bathrooms are located away from the sleeping area. Some of the older employees actually lived in the valley before it was flooded.
To explore the area, there are several hikes including trails to a viewpoint (moderately difficult), Coral Cave (easy) and Nam Talu Cave (challenging). Guides are mandatory for these hikes.
Cheow Lan lake’s other attractions include kayaking, wildlife viewing from the boat, swimming, and longer expeditions to the wildlife sanctuary. Most accommodations have kayaks that guests can use to explore nearby coves in search of wildlife and solitude.
Further afield, at the end of the lake, is the Khlong Saeng wildlife sanctuary. This is where the reservoir ends and nature remains undisturbed by the inundation of the valley downstream. Because this habitat is still intact, wildlife is more commonly seen.
Cheow Lan is a place of world-class beauty that is still relatively undiscovered, allowing visitors to experience nature without the distractions of large crowds.
As you make your way into Khao Sok National Park you will become immersed in one of the world’s oldest jungles. The geological conditions, high rainfall, and limestone karst formations have contributed to the appearance of distinctive forest types and unique plant species. Giant thickets of bamboo, massive buttress roots, dipterocarp trees with propeller seeds that perform beautiful spinning descents from the canopy, and the massive Rafflesia flower await.
Khao Sok has been geologically stable over the last 60 million years. While other regions of the world experienced periods of glaciation and shifting climate, Thailand rested in the middle of the relatively stable Indo-Chinese plate, never drifting far from the equator. This long period of stable weather and rainfall patterns have allowed the many species of the area to prosper.
Khao Sok rests near or straddles many features that create different bioregions. The Tenasserim Hills that serve as a continental divide, separating eastern and western regions of the Thai peninsula, run along the edge of Khao Sok National Park. It lies immediately below the Isthmus of Kra, separating the bioregions of peninsular Thailand and Malaysia from the more deciduous, dry regions to the north.
The Kangar-Pattani line south of Khao Sok near the Thai-Malay border separates the jungles of the Orient from the jungles of Indonesia and its surrounding areas. A key distinction of this line is the shift in humidity, as it is markedly higher south of the line.
Let It Rain
Since Khao Sok National Park straddles both sides of the continental divide, it receives heavy rains during the southwest monsoon coming from the Andaman coast and occasional rains during northeast monsoons coming from the Gulf of Thailand, creating one of the highest rainfall totals in all of Thailand at 3.5 meters per year.
Khao Sok’s unusual ecological features include the flora found on the craggy limestone mountains known as karsts. These spectacular cliffs began their life as sea corals. They were uplifted en masse with the Earth’s crust to form the peaks we see today and were subsequently eroded by rain and the rise and fall of the oceans leaving dramatic, sharp and varied shapes.
The lack of soil, extreme desiccation during dry season and varying altitude have created niches for endemic species of plants. The pralahoo palm, langkow palm, and fern palm are examples of species seen in Khao Sok and nearly nowhere else. Rainwater collects on small shelves along karst faces and mixes with decaying plant matter to make a soil that provides just enough for these palms to grow.
A much-admired oddity is a large almost black flower known in Thai as “bat’s whiskers.” But the most famous of all, sometimes called the world’s largest flower, is the Rafflesia. This Rafflesia blooms in Khao Sok Park occasionally for about 7 days in the dampness of the forest. You can discover it yourself on our special Rafflesia Hike.
Many varieties of bamboo, huge climbing vines (lianas), and Rattan are also common. Rattan, commonly used to make cane furniture, grows to lengths of 100 feet, has very prickly thorns, and a sour red fruit which is refreshing to nibble on a hot rainforest trek. Walk slowly through the forest and appreciate the beauty of these plants. Spot the various strange mushrooms, like the net mushroom pictured here.
Another fascinating oddity prominent in Khao Sok ecology is the strangler fig. The strangler fig is actually a vine although after years of growth it looks like a tree. Its fruit, which is not much different from the fig we eat, is a favorite of the hornbills, gibbons, and other wild animals and birds in the forest. When these animals emit the seed and it falls on a tree, it eventually sends fast-growing roots to the ground. After many years, these roots become large enough to circle and strangle the host tree, which dies and deteriorates, leaving a hollow sometimes big enough to walk into.
Khao Sok National Park has incredibly diverse wildlife. Most commonly seen in Khao Sok, even here at the resort, are hornbills and monkeys. There are numerous species of hornbills, and you may get to see the Great Hornbill with its 1-1/2 meter wingspan that makes a loud whoosh sound as it flies. Make sure you watch out for the mischievous monkeys.
Of the many animals we see at the resort, the most common is the medium-sized Pied Hornbill. All have a characteristic ungainly look, with black and white body and curved yellow beak.
There are four types of monkey in Khao Sok – the shy and adorable langur (aka leaf monkey), the sociable long-tailed macaque (seen year-round at Our Jungle House), and the less common stump-tailed macaque and pig-tailed macaque. Other simians found in the area are the white-handed gibbon, that can be heard calling from the mountains each morning, and the slow loris (a nocturnal, incredibly cute, lemur-like creature).
On a Cheow Lan lake trip, you can expect to see otters, fish eagles, colorful yellow-beaked hornbills, gibbons, and monkeys. On the Khao Sok Special Wildlife Tour it is also possible to see wild elephants, sambar deer, the highly endangered tapir as well as the gaur (Asian bison).
Khao Sok is home to four types of monkeys. Long-tailed macaques are the most common monkeys you will see around Our Jungle House. They are brown in color and often move in groups of 5-20. They are not shy and are seen in many places – sometimes they swing through the trees near your house. They can often be found in the fruit orchard out past the clubhouse. Two other species – the pig-tailed macaque and the stump-tailed macaque – are often found deeper in the jungle, and can be quite aggressive, so do not try to befriend them if you meet them while hiking.
The dusky langur, also known as a leaf monkey, lives in the upper canopy. They are grey-black in color and shyer than the macaque. The lighter color of fur around their eyes gives them a spectacled look, as if they are wearing glasses.
Gibbons is hard to see, since they spend most of their life high in the canopy. But because they are highly territorial, you’ll most likely hear their loud vocal displays. Often described as ‘song’ and mostly heard at dawn, pairs of gibbons sing coordinated duets. The dominant female produces what is known as a ‘great call,’ a series of loud notes with different pitches and tempo. The calls sound like a crescendo of notes or a series of rising and falling whoops. Each gibbon species has a distinctive song, hence it’s a reliable way of identifying which species may be present at a particular location. These songs are also the gibbons’ way of communicating with family members. Gibbons have a lifespan of about 25 years in the wild, and are monogamous mammals forming bonds for life.
Members of the ape family, gibbons have no tail. Their long arms enable them to brachiate (swing) between tree branches. Unlike most primates, who simply jump between branches, a gibbon can brachiate at speeds as high as 35 mph and can travel as far as 30 feet in one swing.
This ancient bird is usually found in mature forests, and their presence at the resort is evidence that the chain of nature is still intact at Our Jungle House. Slightly awkward in appearance, they have brilliant yellow beaks and black and white plumage. Nine species of hornbill are found in Khao Sok National Park, four of which visit the trees around the property.
The Great Hornbill, has a wing span of nearly two meters. The wings are so powerful that the bird makes a loud whooshing sound as it flies by. You may also see a smaller hornbill, called the Oriental Pied. If you hear a sharp “kaek kaek kaek” sound, that’s him (or her). Most often, hornbills are seen at our resort feeding on wild fig trees from October to February.
There are 12 species of Kingfisher found in Khao Sok National Park. You can often see them along the river, perched on branches above the stream. The species can vary in colour; some being the classical bright blues, others like the Ruddy Kingfisher are rusty red in colour. Their diet consists mostly of fish, crabs, frogs and insects. Large fish are beaten on a bough or rail; small fish and insects are promptly swallowed. A fish is usually lifted and carried by its middle, but its position is changed, sometimes by tossing it into the air, before it is swallowed head downwards.
While there are many sounds in the forest, the cicadas’ calls dominate the ‘soundtrack’ at Our Jungle House. Cicadas are large insects with sizable compound eyes and transparent wings. Cicadas are one of the most widely recognized of all insects, due to their remarkable (and often inescapable) acoustic talents. The cicada creates the sound by rapidly vibrating a drum like membrane located on each side of the body. At close range the volume of the cicada’s love calls can be up to 120dB, similar to the volume of a car horn, or an aircraft taking off.
You hear the frogs at night, find them in your garden, see them jump as you walk by ponds. Along with lizards, spiders, birds, and bats, frogs are a major factor in the control of insects, and are also a food source for many animals. Especially after a heavy rainfall, it is impossible to ignore the frogs’ loud calls. But the ‘noise’ will gradually taper off and stop completely. Best to enjoy the sounds as part of the jungle soundtrack.
The gaur (sometimes called Asian bison), is an impressive wild buffalo with thick curved horns. It weighs over a ton and has distinctive white feet and ankles looking just like socks. Using its sharp pointed horns and the hard frontal ridge of its forehead, an adult Gaur can kill an assailant with one blow. Even leopards and tigers rarely tackle one of these enormous beasts. Generally, gaur will choose to avoid conflict rather than engage.
Danger in the Jungle
Contrary to popular belief, the jungle is benign and probably a safer habitat for humans than city streets. This is primarily because animals, like ourselves, instinctively avoid danger and will avoid humans rather than attack them. Some of the potential ‘predators’ found in Khao Sok and most tropical jungles of the world are snakes.
In Thailand, there are more than 170 species of snakes, only 48 are venomous and most of these snakes are rare. Lethal snake bites account for less than 20 cases in Thailand per year. Since snakes are active at night, it’s advisable not to walk in the dark without a torch.
If you do encounter a snake, stand still and wait for it to move away. If you do get bitten, apply a pressure bandage and stay still to prevent the venom from spreading through your body. If possible, take a photo of the snake (to identify the species) and get to a hospital.