Expedition to study the distribution of the Baikal omul using hydroacoustic methods and eDNA analysis

Within the state assignment “Assessment of environmental and economic aspects of the impact on Lake Baikal from existing and planned anthropogenic factors in the Baikal natural area, rational nature management, water and bio-resource potential of Lake Baikal” (led by M.M. Makarov) (0279-2022-0004), on March 7–12, an expedition was held to conduct hydroacoustic observations of the dynamics of the Baikal omul distribution near the Bolshiye Koty settlement, Buguldeika settlement, and Selenga shallow water.

An observation point was placed on the ice of the lake, where the migration of omul was continuously monitored during the day using a scientific echo sounder. Water samples were taken to investigate the eDNA concentration of the Baikal omul at the observation sites.

The largest aggregations of fish were found near the Buguldeika settlement. The density of aggregations was comparable to those ones previously recorded in the Selenga shallow water zone at the end of May. However, similar aggregations were not recorded in the Selenga shallow water.

In the long term, both methods will allow for a more accurate assessment and forecasting of the stocks of this species. The used approach is innovative and does not require the capture of fish.