@article{Ding_Cao_Chen_2019, title={Stock assessment of the western winter-spring cohort of Ommastrephes bartramii in the Northwest Pacific Ocean using a Bayesian hierarchical DeLury model based on daily natural mortality during 2005-2015}, volume={83}, url={https://scientiamarina.revistas.csic.es/index.php/scientiamarina/article/view/1802}, DOI={10.3989/scimar.04783.10A}, abstractNote={The purpose of this study was to evaluate the effect of the intensive commercial jigging fishery on the western winter-spring cohort of neon flying squid (<em>Ommastrephes bartramii</em>) in the Northwest Pacific Ocean and to estimate the exploitation status of this stock during the period 2005-2015. We applied a Bayesian hierarchical DeLury depletion model to the Chinese jigging fisheries data to estimate the stock abundance and catchability for each year, and sensitivity analysis on daily natural mortality (<em>M</em>) was conducted. The results indicated that <em>M</em> values had great impacts on the overall estimates of stock size. Initial annual population sizes varied from 66 to 662 million individuals with the <em>M</em> value of 0.003-0.01 per day during the study period. <em>O. bartramii</em> suffered from a certain degree of overexploitation in 2008. The proportional escapement values (<em>M</em>=0.003-0.01) were 8.94% to 19.82% in 2008, with an average of 13.74%, which may have led to a low abundance of <em>O. bartramii</em> and annual catch since 2009. As short-lived ecological opportunists, <em>O. bartramii</em> are extremely sensitive to changes in multi-scale environmental conditions, especially when anomalous environmental conditions occur, and significant between-year variations in the initial abundance resulted in <em>O. bartramii</em> suffering from a certain degree of overexploitation in 2010. Although the proportional escapement met the management target of 40% from 2011 to 2015, the stock size and annual catch still fluctuated at relatively low levels. Improved knowledge of the influences of environmental conditions on abundance of the western winter-spring cohort of neon flying squid can contribute to the sustainable management of this stock.}, number={2}, journal={Scientia Marina}, author={Ding, Qi and Cao, Jie and Chen, Xinjun}, year={2019}, month={Jun.}, pages={155–166} }