Transboundary Resources Assessment Committee Status Report 2015/03 : Georges Bank Yellowtail Flounder TRAC. 2015. Georges Bank Yellowtail Flounder. TRAC Status Report 2015/03

Combined Canada and USA catches in 2014 were 159 mt. This is the lowest value in the time series beginning in 1935. Discards were greater than landings for the first time in 2014. The declining trend in survey biomass to low levels for the past two years, despite reductions in catch to historical low amounts, indicates a poor state of the resource. Recent catch is low relative to the biomass estimated from the surveys but catch curve analyses indicate high total mortality rates (Z>1). Stock biomass is low and productivity is poor. An empirical approach based on survey catches developed during the 2014 Georges Bank Yellowtail Flounder Diagnostic and Empirical Approach Benchmark was applied to generate catch advice. There are two approaches to management that could be considered: constant exploitation rate and constant quota. The Transboundary Resources Assessment Committee (TRAC) recommends the Transboundary Management Guidance Committee (TMGC) implement and maintain one of these approaches over three years to see if the stock responds. Using a constant exploitation rate of 2% to 16% results in catch advice of 45 mt to 359 mt. Using a constant quota approach, the TRAC recommends a quota of 354 mt or lower (based on not increasing the quota relative to the 2015 quota due to concerns about stock declines). 2015 NMFS (National Marine Fisheries Service) NEFSC (Northeast Fisheries Science Center) Submitted Public Domain 1930

2014年加拿大与美国的总捕捞量为159公吨，这是1935年起的时间序列中的最低值。2014年首次出现弃渔量高于渔获上岸量的情况。尽管捕捞量已降至历史低位，但过去两年间调查种群生物量持续下降至低位，这表明该渔业资源的现状堪忧。相较于调查估算的生物量，当前捕捞量处于低位，但捕捞曲线分析结果显示总死亡率系数（Z>1）较高。种群生物量偏低，资源生产力不佳。本次研究基于2014年乔治浅滩（Georges Bank）黄尾鲽（Yellowtail Flounder）诊断与经验方法基准中形成的调查捕捞相关经验方法，生成了捕捞建议。可供考虑的管理方案有两种：固定开发率与固定配额。跨界资源评估委员会（Transboundary Resources Assessment Committee, TRAC）建议跨界管理指导委员会（Transboundary Management Guidance Committee, TMGC）在三年内推行并维持其中一种方案，以观测种群的响应情况。若采用2%至16%的固定开发率，对应的捕捞建议量为45公吨至359公吨。若采用固定配额方案，跨界资源评估委员会建议配额为354公吨及以下，该建议基于对种群衰退的担忧，因此2015年配额不做上调。本报告由美国国家海洋渔业服务局（National Marine Fisheries Service, NMFS）东北渔业科学中心（Northeast Fisheries Science Center, NEFSC）于2015年提交，归属公有领域，文档编号1930。