Abstract Catch share management was implemented in the bottom trawl sector of the West Coast Groundfish fishery in 2011 to address a range of issues including high bycatch and discard rates. The catch share program was designed to remove the incentives to discard through full catch accounting, tradeable quotas, increased flexibility in fishing, and penalties for catch overages. We assess the effectiveness of the program in meeting its environmental objectives by comparing discard weights, proportions, and variability from 2004–2010 with 2011–2016. We analyzed these metrics for species managed using quota, including historically overfished stocks, as well as for non-quota species caught in the fishery. Discard amounts decreased over time for all species and declined to historic lows after the implementation of the program, remaining low through 2016 with much less inter-annual variability. Mean annual discards of two highly-targeted quota species, sablefish and Dover sole, showed the greatest decreases, falling by 97 and 86%, respectively. The discard proportion of overfished quota species fell by 50% on average. The unanticipated decline in discards of non-quota species as well as the decreased variability in discard amounts for all species indicate that the incentives produced by catch share management provided additional ecosystem benefits.

中文翻译：

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使用激励措施减少兼捕和丢弃：西海岸捕捞分享计划的结果

摘要 2011 年在西海岸底层鱼类渔业的底拖网部门实施了渔获份额管理，以解决包括高兼捕率和丢弃率在内的一系列问题。渔获份额计划旨在通过全面的渔获量核算、可交易配额、增加捕捞灵活性以及对超额渔获物的处罚来消除丢弃的诱因。我们通过比较 2004 年至 2010 年与 2011 年至 2016 年的丢弃重量、比例和可变性来评估该计划在实现其环境目标方面的有效性。我们分析了使用配额管理的物种的这些指标，包括历史上过度捕捞的种群，以及渔业中捕获的非配额物种。随着时间的推移，所有物种的丢弃量都在下降，并在该计划实施后降至历史低点，到 2016 年保持低水平，年际变化要小得多。两种高度针对性的配额物种，黑鲈和多佛鳎的年平均丢弃量下降幅度最大，分别下降了 97% 和 86%。过度捕捞配额品种丢弃率平均下降50%。非配额物种丢弃物的意外下降以及所有物种丢弃物数量的变化减少表明，渔获份额管理产生的激励措施提供了额外的生态系统效益。