OSPAR request on implementation of MSFD for marine mammals
ICES advises on a number of aspects of the common implementation by OSPAR of the Marine Strategy Framework Directive (MSFD).
ICES advises that “assessment unit” is a more appropriate term than “management unit” for subdivisions of the range of marine mammals under consideration by OSPAR. In OSPAR regions II, III,and IV, ICES advises that harbour seals be treated within 17 units and grey seals be treated within two units. ICES also advises on assessment units for the five cetacean species being considered by OSPAR under MSFD.
ICES provides general advice on the need to understand the statistical power of monitoring programmes before targets are set under MSFD in relation to that monitoring. It is not advisable to set targets that demand a higher statistical precision than can be metwithin a feasible monitoring programme. This requires that thestatistical power of amonitoring programme needs to be analysed prior to set targets.
ICES notes that several of the indicators proposed by OSPAR are compound indicators(e.g. indicators that cover more than one species),which do not include specific rules defininghow the indicator should operate. ICES recommends breaking the compound indicators down to specieslevel, before setting rules for their use. ICES also suggests the simplification of the indicators ofcetacean abundance. ICES advice is based on these simplified indicators.
ICES advises that distributional range is a difficult concept to set MSFD targets for in relation to seals and cetaceans with the exception ofinshore assessment units of bottlenose dolphins. The number of regular sites for grey seal pupping and harbour seal moulting would be suitable for target setting in relation to the distribution of these species.
ICES advises also that the current technique for monitoring grey seal abundance is to survey pup numbers and therefore there is duplication in the currently suggested grey seal targets. ICES advises on technical aspects of target setting for the abundance of the two seal species and notes that further harmonization of monitoring methods will be required, as well as an upgrade on current data storage.
The decadal frequency of current surveys of cetaceans that range over wide areas mean that it isvery difficult to detect,with any statistical certainty,any change in abundance on a reasonable time scale (a six-year time scale is implied in some EU legislation). This implies that survey frequency needs to be increased –the (societal) choice of statistical power has implications for survey frequency.ICES also notes that IUCN uses a three-generationalapproach to the detection of changes in population abundanceand recommends that OSPAR might switch to such an approachin setting targets. ICES makes suggestions for the wording of targets using this approach.
ICES has provided advice to the European Commission under EU Regulation 812/2004on setting targets for limits on bycatch using an approach known as the Catch Limit Algorithm. Key choices need to be made at the societal/policy level for this advice to be further developedand ICES has offered to help organize a workshop to consider these choices.
ICES has provided a summary of existing monitoring schemes but cannot provide a full overview of future monitoring needs until societal and policy decisions have been taken in relation to targets and their statistical precision. ICES has not, on this occasion,been able to provide overviews of the monitoring of marine mammal bycatch
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