Proceedings 2015/029

Proceedings of the Regional Framework Meeting for Use of Research Vessel Survey Data to Assess Secondary Groundfish Stocks in the Maritimes Region; December 16-17, 2014

Chairperson and editor: Kristian Curran

Summary

A “Proxy Approach” for estimating reference points for secondary stocks was proposed: the geometric mean of the stratified total biomass from the RV Survey (summer or winter, dependent on the stock) as a proxy for biomass at Maximum Sustainable Yield (B_MSY) for a chosen time period. Biological reference points were subsequently calculated where 40% of the proxy B_MSY was proposed as the Lower Reference Point and 80% of the proxy B_MSY was proposed as the Upper Stock Reference. The three-year running median of the biomass was then used to examine the long term trend in biomass against the reference points. Meeting participants discussed applicability of this approach for all secondary species, as it does not take into account the nuance of biomass history (e.g. fishing pressure). It was concluded that for some stocks the biomass history, as well as additional analytics to evaluate uncertainty, is needed to characterize proposed reference points. Guidance for evaluating uncertainty includes: 1) evaluate whether survey indices reflect fishery impact on the stock; 2) evaluate the impact of choice of period in the time series; and 3) evaluate additional information to inform the impact of the Proxy Approach. Given that many secondary stocks assessed at the meeting required further analysis, it was agreed that a Science Advisory Report would not be completed and published as part of the meeting’s products. Last, it was agreed by some meeting participants that despite limitations in the proposed Proxy Approach, it remains very important to derive reference points for many of the secondary stocks in question, as there are some urgent management needs for many of the species that were discussed (especially for skates). Additional research in this regard was encouraged by all meeting participants.

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