Expeditionsrapport SPRAS 2020-2021

The report includes results from the first two years of Swedish participation in the internationally coordinated Sprat Acoustic Survey (SPRAS-Swe,) in the Baltic Sea. The survey has been running since 2001 but Sweden participated for the first time, with the new ship R/V Svea, in 2020. The aim of the survey is to collect fishery independent data on sprat and herring in the Baltic Sea to use in stock assessment. Each country in the cooperation covers a part of the total area. All data is compiled and used for assessment by the ICES working group WGBFAS. The Swedish part of the survey has also been used as a pilot study to include more parts of the Baltic Sea ecosystem (eg. birds and zooplankton) to investigate if the survey can be used as an ecosystem platform to develop out knowledge of the Baltic Sea. Another aim of the pilot study part of the survey is to develop sampling and analysis to reduce the number of fish killed during acoustic surveys.