The surveys are for the long-term monitoring of demersal fish to provide data on commercial species for stock assessments and for examining changes in fish distribution and abundance. The group also promotes the standardization of fishing gears and methods used and designates survey coordinators.
While the international programme was originally designed as a young herring survey, the focus has since widened to cover demersal stocks. Survey data therefore now feed into the assessment of both demersal and pelagic stocks. As its aims have broadened, the surveys now constitute a source of long-term data on the status of fish in relation to their environment. New challenges exist in survey design and sampling strategies to address ecosystem monitoring needs, for example in connection to the EU Marine Strategy Framework Directive (MSFD).
Reflecting these more diverse tasks, the group depends on experts from a number of disciplines – including survey and assessment as well as gear technology and ecosystem modelling.