Development of an Approach for Biomass Estimation of Inland Fisheries

On 17–20 November 2025, SEAFDEC/IFRDMD conducted an activity on the development of an approach for biomass estimation of inland fisheries using hydroacoustic surveys. This activity is part of the project “Enhanced Research Capacities for Sustainable Utilization and Management of Eel and Other Inland Fisheries Resources,” supported by the Japan Trust Fund VII. The survey was led by the Deputy Chief of SEAFDEC/IFRDMD, Mr. Toru Shimoda, and implemented in collaboration with staff from the Research Institute for Inland Fisheries and Extension, Ministry of Marine Affairs and Fisheries, Republic of Indonesia.

The survey took place in the Musi Estuary, Banyuasin Regency, South Sumatra, Indonesia, using a BioSonics DTX portable echosounder with a frequency of 200 kHz mounted on a small fishing vessel. The initial activity carried out by the IFRDMD team was the calibration of the echosounder, followed by a hydroacoustic survey along a zigzag track. The survey track covered the mouth of the Telang River, the upper zone of Payung Island, and the mouth of the Musi River. In addition, the team collected data from fishers, including fish species identification, as well as length and weight measurements.

This activity was the final survey in 2025, completing the series of surveys conducted in the Musi River system, Indonesia. Earlier, IFRDMD had carried out surveys in the upstream, middle, and several tributaries of the Musi River, including the Ogan and Lematang Rivers. The overall objective of these surveys is to improve stock data collection for inland fisheries to support sustainable resource management, thereby contributing to food security and the livelihoods of local