Free-flowing fish for food security

Everything is going swimmingly for an ACIAR project in Laos, investigating ways to allow fish to move freely between the Mekong River and nearby floodplains.  The first ever fishway (a structure allowing fish to move through, around or over barriers) for Mekong species in Laos has just been built using know-how from ACIAR-funded research.

Fishway construction in Laos
(photograph by Jim Holmes)

Fish movement across Mekong floodplains is currently blocked or limited by thousands of irrigation regulators (weirs and flood gates) put in place for flood control and irrigation purposes. This has led to a decline in fish populations because they are denied access to vital spawning and nursery habitat.

The Mekong floodplains are vital spawning and nursery habitat
(photograph by Jim Holmes)

The impact has been felt not only by the fish, but by Lao fishermen relying on their catch for both food and income.

Because different fish species have varying swimming abilities, the research has focused on learning about the behaviour of Mekong species, then using that information to design fishways.

The fishway just built will help fish to move between the Mekong River and the Pak Peung wetlands.

Dr Oudom Phonekhampheng explains how the fishway works
to Australian Ambassador to Laos, Ms Lynda Worthaisong.
(photograph by Stephanie Rajalingam)

The Australian Ambassador to Laos, Ms Lynda Worthaisong, recently visited the project site and was impressed. “This project is unique in the region, and takes advantage of research and technology to build a functional fish passage, which is quite a significant construction effort.”

She said the fishway will play a vital role in ensuring food security and boosting the economy of the region.  

“It will mean that a lot of people in this area have access to more fish...which is so important for nutrition and other reasons.”

Fisheries experts discuss the fishway construction with Lynda Worthaisong.
(photograph by Stephanie Rajalingam)

“We’re really pleased to have been able to support this project and look forward to seeing it being completed soon.”

Hard at work at constructing a Mekong fishway
(photograph by Jim Holmes)

Now that the fishway is built, the researchers can assess how well it works this wet season in a real life situation. The $2.2 million project has been running since 2010 and final results will be determined over the next two years as the fishway is put to the test. Once the team has demonstrated its effectiveness, they hope to replicate it over many floodplains along the Mekong (with the help of donor agencies, including AusAID).

The project also has an Australian component. The NSW Department of Primary Industries are looking at fish passages in the Murray-Darling Basin. There are some striking similarities between the Mekong and Murray-Darling Basins: both drain a similar geographical area and rely on regular flooding to maintain fisheries productivity. So, the results of the Laos research will hopefully have flow-on benefits not only for the local fish and folk, but also for Australia.

Further information: ACIAR Project FIS/2009/041

(Written by Dr Wendy Henderson, ACIAR Communications)