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Venues for presenting and reviewing ecosystem models. Ad hoc, informal review characterizes all responses Typical phrases: “no formal means...” , “using local experts...”, “no formal venues exist” Some review associated with stock assessments
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Ad hoc, informal review characterizes all responses • Typical phrases: “no formal means...” , “using local experts...”, “no formal venues exist” • Some review associated with stock assessments • Presentations at workshops is pretty standard for all centers • Some review associated with submission of journal articles • Many comments regarding lack of expertise of reviewers (especially within more general working groups)
Antarctic stands in stark contrast • EM efforts are presented to and reviewed by • the Working Group on Statistics, Assessments and Modeling • Working Group on Ecosystem Monitoring and Management • Reviews are documented as part of each working group's report, and these reports are adopted by consensus • A further level of review is sometimes provided by the CCAMLR Scientific Committee
Example: Evolution of single-species assessments to include advice from multispecies models and indicators • From North Pacific Fisheries Management Council’s Scientific and Statistical Committee minutes, December 2006: • “The [eastern Bering Sea walleye pollock] stock remains above the MSY level, having declined … at a rate of about 19% per year….A series of 4 below-average recruitments has contributed to the decline…the series of low recruitments will result in an age-structure that is dominated by only a few year-classes which could increase fluctuations in the population.” • “Other issues raised in the stock assessment suggest a need for further caution.” • a northward shift … with some portion of the population into Russian waters. • a large decline in zooplankton, which is important in providing forage for juvenile pollock. • increasing predation by arrowtooth flounder on juvenile pollock, which could contribute to further declines in adult pollock biomass. • “Consequently, the SSC agrees with the Plan Team that a reduction in Allowable Biological Catch from the maximum permissible is justified.” Result from single-species assessment Assessment + ecosystem indicators Ecosystem indicators (FATE) Multispecies models – Modified Ecosim and MSFOR