Abstract The Pacific halibut (Hippoglossus stenolepis) stock in the waters of the exclusive economic zones of Canada and the United States of America has been actively managed by the International Pacific Halibut Commission since its formation in 1923. Fisheries accessing this resource have become increasingly varied over time and among geographical areas, and more than capable of utilizing the entire yield available each year, which has averaged 34,000 mt since 1992. In recent years, 69.5 % of the mortality has come from the directed commercial fishery landings, 15.4 % from non-directed commercial fisheries (legally restricted from retaining any halibut) and 15.1 % from all other sources combined (commercial discards, recreational, subsistence). Understanding the relative effects on the stock and potential yield of allocation among fishery sectors is a high priority for managers and participants in these fisheries. This analysis used the 2019 stock assessment for Pacific halibut and three analytical methods to compare the directed and non-directed commercial fisheries. We found that potential yield to the directed fishery was generally larger than a simple reallocation from non-directed discards (115 % on average), that the rate of exchange is variable over time (range of 86–139 %), and that the effect of the directed commercial fishery on the spawning biomass has also changed over time. We conclude that managers should be aware that no simple ‘conversion rate’ exists for translating mortality among fisheries that differ appreciably when operating on a stock with dynamic biology.

中文翻译：

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完全订阅：评估利用太平洋大比目鱼资源的渔业部门之间的产量权衡

了解渔业部门之间分配对种群和潜在产量的相对影响是这些渔业的管理者和参与者的高度优先事项。该分析使用 2019 年太平洋大比目鱼种群评估和三种分析方法来比较定向和非定向商业渔业。我们发现定向渔业的潜在产量通常大于非定向丢弃物的简单重新分配（平均 115%），交换率随时间变化（范围为 86-139%），并且影响随着时间的推移，产卵生物量的定向商业渔业的数量也发生了变化。我们得出的结论是，管理人员应该意识到不存在简单的“转化率”来转换渔业中的死亡率，当对具有动态生物学的种群进行操作时，这些渔业之间的死亡率存在明显差异。