Songkhram River

“Thai Ban Research” (The Locals’ Research) conducted by locals living along the Lower Songkhram River has recorded up to 79 different fishing gears out of those used by the fishing community in the lower basin, reflecting local wisdom in adjusting their knowledge to different time periods and circumstances. 
Photo: ©KAS Thailand/Sayan Chuenudomsavad

Mekong’s ‘Wilting Womb

NOVEMBER 2, 2021

The rainy season is drawing to a close in Thailand, but 58-year-old Saneh Sukcharoen, the head of Ban Pakyam village by the Songkhram River’s lower section in the upper Northeast, is uneasily seeing winds of change blowing across the region. Nowhere in sight are the “flood pulses” the locals almost take for granted.

The backflow from the Mekong River has been absent this year. The rare and unique annual phenomenon is marked by overflows from the Mekong River that usually run deep into the Lower Songkhram River during the peak flooding period. This creates flood pulses and brings nutrients as well as a variety of migratory fish species from the Mekong to the 400-km-long Songkhram River and its lowland floodplains_the Bung-Tham forests. It is a vital food and income source for locals, like Mr. Saneh.

The whole village has gone quiet. Hardly any “fish hunters” of this well-known fishing village in the Lower Songkhram eagerly go to the river or the forests to catch the Mekong fish that are usually pricier than the native Songkhram River variety.

“We have hardly seen any water from the Mekong River coming upstream this year, or its fish. We have mostly caught the fish resident in Songkhram River,” says Mr. Saneh, pointing to a basket with fish freshly caught from the river. Only a few of the catch are migratory.

Residents of the area, like Mr. Saneh, have long enjoyed the advantages of living by the lower section of the Songkhram River. Unlike other Mekong tributaries in the same region of Thailand’s Northeast, the Lower Songkhram River_nearly 200 kilometres long_is considered to be the most pristine and fertile in the region, as it remains untamed by any of the water resource development projects. In fact the entire Songkhram River, which runs over 400 kilometres before discharging into the Mekong River at Chai Buri Village in Tha Uthen district in Nakhon Phanom province_near Mr. Saneh’s village, remains largely untamed.

Aside from its pristine and fertile attributes, it also possesses the uniqueness of the natural river cycle linked extensively to the Mekong River’s hydrology. The so-called backflow, under which the overflow of the Mekong River runs deep into the Lower Songkhram River during the peak flooding period, creates the “flood pulse” phenomenon that has long nurtured the river’s ecosystems, especially its lowland Bung-Tham forests.

Yam River

“Sadung Yai” is a giant lift net developed by fishers in the Mekong region, with the actual size depending on the locality. In the Songkhram River Basin, the fishing gear can be as large as three to four square metres. They are placed in “Wang Pla” where fish are abundant during the late rainy season, when the water in the river starts to flow downstream and migratory fish start to travel down to the Mekong River. Sadung Yai will be placed to trap the fish that swim past it.
Photo: ©KAS Thailand/Sayan Chuenudomsavad

‘Thong” is another giant fishing gear made of woven bamboo to form a giant oval-shaped fish trap. It was once popular among those fishing along the Mekong River. These days only those fishing in the Songkhram River still use it. Not many of this gear is around now as they need specific knowledge about the river conditions and the flows to appropriately equip the gear so that its bottom is opened to lure the fish to swim into it. The thong is usually placed by the river with a suitable depth.
Photo: ©KAS Thailand/Sayan Chuenudomsavad

As fertile breeding, feeding and spawning grounds for migratory fish as well as other wild species, which in turn feed the local people, they are sanctuaries. According to the research-based Thai Water Partnership, which helps the locals develop river health assessment tools, at least 17 species have been spotted in the lower section of the Songkhram River, including the IUCN Red List species such as Giant Catfish and Blanc’s Striped Featherback, which regularly use the lower basin as their breeding and spawning grounds. The locals call it the Mekong’s womb. (Read: Sidebar

Due to the rich biodiversity of the area, the residents living along this section of the river have developed their unique way of life, revolving largely around fishing. Over the years, they have fine-tuned their skills to develop fishing gears that suit the different circumstances and time cycles as well as fish preservation.

According to “Thai Ban Research” (The Locals’ Research) conducted by the locals living along the Lower Songkhram River, up to 79 different fishing gears have been identified and recorded from their routine uses, reflecting the local wisdom in adjusting their knowledge to the different circumstances around them. 

On some days during the rainy season, the villagers can catch and earn over Bt1,000 a day. The Mekong fish, in particular, can earn them as much as Bt200-300 per kilogram. It’s only this year that the residents of this lower section of the Songkhram River have started to feel the real pinch.

Songkhram River

During the peak flooding period from July to September, the Mekong’s backflow usually intrudes the Lower Songkhram River, flooding around 80,000 to 96,000 hectares (ha) of the Lower Songkhram basin, or around 500,000 to 600,000 rai, including the Bung-Tham forests, which will turn into good nursery grounds for the Mekong’s migratory fish. It also becomes a good fishing ground for fishers in the Lower Songkhram.
Photo: ©KAS Thailand/Sayan Chuenudomsavad

During the rainy season, “Phai Kasa”, a bamboo shrub native to Bung-Tham forests, also gets flooded and covered by water, serving as a good breeding and spawning ground for the fish due to their cluttered branches and leaves.
Fishermen learn to sneak through this flooded bamboo shrub, by boat or on foot, to set traps or cages to trap the fish.
Photo: ©KAS Thailand/Sayan Chuenudomsavad
Aside from migratory fish, the fishers of the Lower Songkhram also collect other wild species including a giant field frog which is caught in a fish trap placed in the flooded Bung-Tham forests. 
Photo: ©KAS Thailand/Sayan Chuenudomsavad

The disappearing Mekong fish

A study, “Fish in the Lower Songkhram River; Catching, Disappearing, and Compensating” by Rajabhat Mahasarakham University and Nakhon Phanom University, a few years ago had already reported the disappearance of some local fish in the river around 10 years back. The researchers said this was partly because there had been overfishing, while fertile fish nursery grounds had been converted into farmland, resulting in the depletion of biodiversity in the area.

However, that still does not compare with this year’s unique scenario where Mr. Saneh has hardly seen any migratory fish from the Mekong. 

In the mid-2020s, unusual water fluctuations had already been observed, and the changes were recognized, including the water level of the river which decreased earlier than usual in the dry season, according to the Thai Water Partnership. 

“When the river ecosystem is affected by unusual water fluctuations, the migration patterns of fish may also be affected, as well as cause the degradation of seasonally flooded forests,” noted the organization.

Following exchange of information and updates from residents living along other tributaries, Mr. Saneh said the residents in the Lower Songkhram River had learned about dams on the mainstream Mekong that may have affected the flow regime of the river.

Although he has not found solid proof, he strongly believes the dams on the Mekong River are responsible in some way for the drop in water levels this rainy season.

“They said the dams upstream (in China) are storing water extensively, and that’s why there is hardly any water flowing down into our river,” says Mr. Saneh. The water level of the Mekong River this year had dropped too low to be able to flood the Songkhram River through their confluence, he adds.

The village head says the locals are also concerned about plans to construct new sluice gates on the Songkhram River. The villagers have learned that a few of them are already in use upstream. If more come up at the Mekong confluence as announced, the river cycle of the Lower Songkhram River will see further disruption to the point that they can no longer fish and make a living.

“What if there are no more natural river flows that lure the fish, and no more fish come in? We are doomed, just like our neighbours in other tributaries,” said Mr. Saneh.

The Thai Water Partnership, meanwhile, noted: “The complexity of local livelihood that has adapted to these environments is easily overlooked. Rural livelihoods are based on the combined use of a wide range of resources adapted to seasonal changes. Communities located along with the Songkhram floodplain exhibit a high degree of dependency on wetland resources for their livelihoods.”

More photos from the air@ The Lower Songkhram River from the Air

Songkhram River

During the dry season, the Lower Songkhram residents go into the Bung-Tham forests to collect forest products, including baby bamboo shoots of “Phai Kasa”. But during the rainy season, the bamboo shrub will be flooded and covered by water. It provides a place for the fish to hide, acting like a coral reef that provides a good breeding and spawning ground for the fish. 
Photo: ©KAS Thailand/Sayan Chuenudomsavad

“Luang Pla” is a reserved fishing ground where fishers make an agreement with one another. Within Luang Pla, fishers from other families will not be allowed to catch fish without permission. It’s recognized as family-owned and can be passed on from one generation to the other. Luang Pla demonstrates local resources management that the residents of the Lower Songkhram have developed and put in place to pacify possible disputes in their communities.
Photo: ©KAS Thailand/Sayan Chuenudomsavad
“Toom Jew” or a small fishing pot is a small-sized fishing gear that fishers at the Lower Songkhram River use to trap small or baby fish, which will be brought to be raised further in fish cages placed along the river. The fish culture practice has become increasingly popular in recent years. Some fish farmers turn to this practice seriously and rely on agro companies for fish culture equipment and fish food.
Photo: ©KAS Thailand/Sayan Chuenudomsavad

“Pla Pia”, or the black shark, is a freshwater fish native to the major basins of Chao Phraya as well as the Mekong River. This fish, which weighs around four to five kg, is caught in a fish trap placed at the mouth of Lower Songkhram River shortly after the Mekong slightly surges around the river mouth before dropping. The fishers there usually call this period “Pla Tuen Nam”, or the water shock for the fish, when the Mekong River is about to flood and flow into the Songkhram River. The fishers usually observe the colour of the water and its reversing flow direction. If it is reddish in colour when the Songkhram River flows back, they will know that the Mekong River has started to flood in.But this year, the Mekong has not flooded into the river and a vast area of Bung-Tham forests have not flooded extensively as in the past. 
Photo: ©KAS Thailand/Sayan Chuenudomsavad

Certain fish species are caught in the Lower Songkhram during the rainy season when the Mekong River floods into it. They are migratory, suggesting the unique cycle of the Mekong River and the Songkhram River which involves the backflow and their flood pulses. The only place which encounters the backflow of the Mekong is Tonle Sap in Cambodia.
The basin and its Bung-Tham forests are the resting place for lives from the Mekong before returning them to it again. Such a unique life cycle prompts locals to dub the basin and its forests as the Mekong’s womb.
Photo: ©KAS Thailand/Sayan Chuenudomsavad
A young giant catfish weighing around 30 kg is chopped and placed for sale in Sri Songkhram Market. A fish trader says it’s from the Songkhram River, adding that the fact it has very little fat suggests the fish had been swimming in the strong river current. Sri Songkhram Market is a hub for the Songkhram fish, where fish caught from the Songkhram River is sold. They, therefore, are in a position to know the state of fishing in the river.
Photo: ©KAS Thailand/Sayan Chuenudomsavad
In the past, locals have had to learn to preserve their food, and this has become part of local culture. So has fish preservation for residents of the Lower Songkhram. Their fish preservation skills are well known in the upper North and farther away. Several villages in the area are well known as a “Pla Ra” (fermented fish) making hub, including Pakyam Village.
Photo: ©KAS Thailand/Sayan Chuenudomsavad
“Pla Som ” is another well-fermented fish with a strong sour taste, made by Lower Songkhram residents. Some 10 years back, the residents there started to buy fish elsewhere to make Pla Som, suggesting declining fishing in the area. The residents say that over the past few years, they have not had enough fish to make “Pla Ra” or “Pla Daek”, the well-known fermented fish of the Northeast.
Photo: ©KAS Thailand/Sayan Chuenudomsavad
The “flood pulse” phenomenon caused by the Mekong’s backflow and seasonal flooding contributes to complex water-based geographical characteristics, ranging from permanent and temporary surface water sources, artificial and natural wetland habitats, and a range of riverine, floodplain, lacustrine, palustrine, and salt-water wetlands in the Lower Songkhram. They are local water storage for the residents for the dry season too.
Photo: ©KAS Thailand/Sayan Chuenudomsavad
The wetlands in the basin are not too deep. Some are flooded to knee-level. People can wade through to make a living, from collecting forest products to fishing. 
Photo: ©KAS Thailand/Sayan Chuenudomsavad
Different ecosystems offer different opportunities for the residents of the Lower Songkhram. Some are sophisticated at fishing in the deep water, others are not and they have developed fishing gears that fit their circumstances, such as this net-based trap to catch freshwater shrimps in the swamp. 
In the eyes of developers, these sub-ecosystems of the wetlands are often overlooked. So is the residents’ way of life.
Photo: ©KAS Thailand/Sayan Chuenudomsavad
Songkhram River

A triangular fishing pot that is used in shallow and static water. It is very different from the types used for large water bodies.
Photo: ©KAS Thailand/Sayan Chuenudomsavad

In wetlands, “Sanom” or a naturally formed raft of broken tree branches, shrubs, vines and other leftovers float around on swamps, marshes, or lakes. The villagers sometimes make use of it to trap fish. Some Sanom are tightly packed over time so that people can go up and stand upon them as if they are small islands in the wetlands. Some plant species such as rare tropical pitcher plants, which need little nutrients, grow on these Sanom, adding a distinctive ecological character to the Lower Songkhram.  
Photo: ©KAS Thailand/Sayan Chuenudomsavad

The Mekong’s womb

Running over 400 kilometres through the upper Northeastern region, the Songkhram River is the Mekong’s tributary and contributes around 1.8% of average annual water flows to the Mekong River at Tha Uthen district in Nakhon Phanom province.

Formed geographically as a vast flood plain, approximately 54% of the overall Songkhram Basin, which is the second largest basin of the Northeast with the total area sized around 6,473 square kilometres or around four million rai, could be classified as “wetlands”.

The most extensive area, as noted by the Ramsar Site Information Service, is concentrated in the lowland floodplains of the lower section of the river.

Every year, the Mekong’s backflow intrudes the Lower Songkhram River during the peak flooding period from July to late September. Around 80,000 to 96,000 hectares (ha) of the lower section (500,000 to 600,000 rai) are flooded. It is reported to travel as far as 300 kilometres inland during some flooding years. Such a rare and unique phenomenon also occurs at Tonle Sap in Cambodia.

This “flood pulse” phenomenon contributes to complex water-based geographical characters, ranging from permanent and temporary surface water sources, artificial and natural wetland habitats, and a range of riverine, floodplain, lacustrine, palustrine, and salt-water wetlands.

According to Ramsar, the forest structure of the lower section of the river differs with the changing condition of the terrain. There are two sub-plant communities: pond vegetation and lowland floodplain forest. The terrestrial plant varieties found in the floodplains are dry evergreen forest and dry dipterocarp forest, while mixed deciduous forest may also be found. Across the lower section of the river, at least 232 species of plants can be found, including 55 species of trees, 73 species of shrubs, 26 species of vines and 38 species of water plants.

These diverse habitat characteristics and sub-ecosystems in turn nurture freshwater animals and wildlife in the area, especially the Bung-Tham forests that are predominantly swamp and forest shrubs where they can find particular or micro-niches of the ecosystems for their species.

According to the Thai Ban research, at least 28 different sub-ecosystems have been recorded in the Bung-Tham forests downstream.

Taking into account the rich biodiversity, the villagers along with WWF Thailand last year managed to push for designation of a 34,400-rai area of forests and wetlands to be designated as the country’s 15th Ramsar Site, the world’s 2,420th. 

Among the great biodiversity found in the designated area are 192 varieties of fish, which are both residents of the Songkhram River itself, and migratory ones from the Mekong River.

As noted by Ramsar, many of the fish species are found exhibiting special feeding habits to particular niches in the ecosystem, such as an archerfish which ejects water from its mouth to bring down insects from overhanging vegetation (Toxotes charaneus), and a cyprinid trout-like fish, which catches small fish and insects from the surface of clearwater streams and rivers (Raiamus guttatus).

The lower basin, however, has been under threat like other basins elsewhere. Ramsar notes the factors influencing the ecosystems at the site include habitat destruction, overexploitation, alien species, chemical pollution, infectious diseases, habitat change and others such as global warming. Among these threats, it said, those causing the greatest impact are habitat destruction, overexploitation and habitat change. Other threats have the potential to cause minor or unknown impacts.

Among the species under threat are the critically endangered Baer’s pochard (Aythya baeri), the endangered sutchi catfish (Pangasianodon hypophthalmus) and the vulnerable king cobra (Ophiophagus hannah).

Suriya Kotramee from the WWF working group, which pushed for the Ramsar site listing, says that the Lower Songkhram River has been increasingly facing various threats in recent years. These include large-scale water resources development projects on the river itself, which have added further complications to the flow regime of the river.

Mr. Suriya says the villagers have felt the changes in the river section and are raising questions about the dams on the Mekong, both in Laos and in China. They suspect that these dams are the main reason for the unusual absence of Mekong’s backflow and flood pulses this year.

At present, they are also concerned about new development projects which are being additionally pushed in the area, including the construction of sluice gates at the river’s mouth and in the middle part of the river.

The National Water Resources Office says it has come up with an integrated water development plan to address what it claims are chronic issues in the basin: floods and drought. Planned projects include the construction of large sluice gates at the mouth of the Songkhram River, the middle of the river, and upstream to help regulate the flows of the Songkhram River itself and the Mekong River. In total, up to 1,644 structural and non-structural water management projects have been planned for both short-term and long-term periods (20 years) for the Songkhram River Basin. Among the top priorities are the two sluice gates on the Lower Songkhram River.

On the mainstream Mekong, meanwhile, China has constructed 11 hydropower dams in the Upper Mekong Basin, of which two are large storage dams. Another 11 dams, each with a production capacity of over 100 megawatts, are being planned or constructed, according to the Mekong River Commission (MRC).

Eleven other projects have been planned for the Lower Mekong _seven in Lao PDR, two in Cambodia and two across the Lao-Thai border. Of these, two _Xayaburi and Don Sahong_ have become operational, and four more have been notified to the MRC for Prior Consultation Process, according to the MRC.

Mr. Suriya says the basin has been facing increasing challenges and the impacts from the combination of various factors would become more and more complicated. Climate change, he adds, will become one of the critical factors in the near future as its impacts cannot be easily identified but will be felt strongly.

“The calls for balancing nature by the villagers will become more and more challenging as well as frustrating,” says Mr. Suriya.

Mekong’s ‘Wilting Womb’ is part of the exclusive photo essay series, The Mekong’s Womb, to present to the public the values of the river basins and tributaries of the country and the Mekong region, their rich biodiversity, unique landscape and geography, livelihood and culture, which could soon vanish without a trace because of rapid development in the region.