OSPAR request on common indicator assessments of seals

ICES advises that the data analysis for determining trends in abundance of seals is relatively mature and well developed. ICES advises that the analysis underpinning the assessment of changes in distribution of seals is relatively undeveloped, partly because the purpose of the proposed indicator is unclear, including the scale at which the assessment should be carried out. Decisions around potential future use of the distribution indicator should be made to guide any future development of this indicator. Information on grey seal (Halichoerus grypus) pup production is a fundamental input to assessing grey seal abundance, so there is a large overlap and no independence between these two potential indicators. ICES advises that if OSPAR wishes to reduce the analytical effort associated with assessments, either indicator could be chosen.