“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.

“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.

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

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

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

“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

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