SISP 8 - Manual of International Baltic Acoustic Surveys (IBAS)

Hydroacoustic surveys have been conducted in the Baltic Sea internationally since 1978. The starting point was the cooperation between Sweden and the German Democratic Republic in October 1978, which produced the first acoustic estimates of total biomass of herring and sprat in the Baltic Proper (Håkansson et al., 1979). Since then there has been at least one annual hydroacoustic survey for herring and sprat stocks mainly for assessment purposes and results have been reported to ICES to be used for stock assessment (ICES, 1994a, 1995a, 1995b, 2006; Hagström et al., 1991).

At the ICES Annual Science Conference in September 1997, the Baltic Fish Committee decided, that a manual for the Baltic International Acoustic Surveys (BIAS) should be elaborated. The structure of the manual follows that of the Baltic International Trawl Surveys (BITS). In order to obtain standardization for all ICES acoustic surveys some demands from the Manual for Herring Acoustic Surveys in ICES Divisions III, IV and VI (ICES, 1994b) are adopted.

The objective of the Baltic International Acoustic Surveys and Baltic Acoustic Spring Survey (BASS) programs are to standardize survey design, acoustic measurements, fishing method and data analysis throughout all national surveys where data are used as indices for assessment purposes.