Managers need to be provided with information that will ensure that fishing mortalities remain below the appropriate biological reference points for the key species.

To provide this information, knowledge is required of the relationship between fishing effort and fishing mortality. An experimental approach which provides a clearly measurable level of fishing mortality will achieve this. The fish in the 100-200m depth zone are schooling species and commercial effort will naturally be targeted on schools, so commercial catch rates cannot be used for the abundance measures required to calculate fishing mortality. There is a need therefore for survey fishing before and after the period of intense commercial fishing and for research personnel to oversee the survey fishing, gather samples and information on the survey cruises, process these at the laboratory and analyse the results. Monitoring of the fishing effort through research logbooks during the commercial fishing period is also required.