Testing candidate indicators to support ecosystem-based management: the power of monitoring surveys to detect temporal trends in fish community metrics

摘要: Community metrics describe aspects of community structure and are often calculated from species-size-abundance data collected during fish stock monitoring surveys. Several have been proposed as indicators to support ecosystem-based fishery management. These should be sensitive fishing impacts respond rapidly management action, so that managers can assess whether changes in the a desirable or undesirable response It also possible estimate with sufficient precision detected on time scales year few years. Here, we test power large-scale annual trawl survey (North Sea International Bottom Trawl Survey, IBTS) detect trends six metrics: mean length, weight, maximum slope biomass size spectrum, trophic level. Our analyses show is generally poor. While do provide good long-term structure, they unlikely an appropriate tool short-term decisions. If effective for management, cannot extended, then many surveys will need improved by increased replication standardization.