Brigden K E, Marshall C T, Scott B E, Young E F, Brickle P
South Atlantic Environmental Research Institute, P. O. Box 609, Stanley Cottage, Stanley, FIQQ 1ZZ, Falkland Islands.
University of Aberdeen, Zoology Building, Tillydrone Avenue, Aberdeen, AB24 2TZ, Scotland, U.K.
J Fish Biol. 2017 Jul;91(1):278-301. doi: 10.1111/jfb.13344.
Commercial fisheries data, collected as part of an observer programme and covering the period 1997-2014, were utilized in order to define key reproductive traits and spawning dynamics of the Patagonian toothfish Dissostichus eleginoides at South Georgia. Multi-year spawning site fidelity of D. eleginoides was revealed through the identification of previously unknown spawning hotspots. Timing of female spawning was shown to have shifted later, leading to a shorter spawning duration. A decrease in length and mass of female and male spawning fish and a reduced number of large spawning fish was found, evidence of a change in size structure of spawning D. eleginoides. During the study period fewer later maturity stage females (including spawning stage) were observed in conjunction with increased proportions of early stage female D. eleginoides. The findings are discussed in the context of reproductive success, with consideration of the possible effects such spawning characteristics and behaviours may have on egg and larval survival. This work presents the first long-term assessment of D. eleginoides spawning dynamics at South Georgia and provides valuable knowledge for both the ecology of the species and for future fisheries management of this commercially important species.
作为观察员计划的一部分收集的商业渔业数据涵盖了1997 - 2014年期间，这些数据被用于确定南乔治亚岛巴塔哥尼亚齿鱼（Dissostichus eleginoides）的关键繁殖特征和产卵动态。通过识别此前未知的产卵热点，揭示了巴塔哥尼亚齿鱼多年的产卵地点忠诚度。结果表明，雌鱼产卵时间已推迟，导致产卵持续时间缩短。研究发现，产卵雌鱼和雄鱼的体长和体重有所下降，大型产卵鱼数量减少，这是巴塔哥尼亚齿鱼产卵群体大小结构变化的证据。在研究期间，观察到处于后期成熟阶段的雌鱼（包括产卵阶段）数量减少，同时处于早期阶段的巴塔哥尼亚齿鱼雌鱼比例增加。本文结合繁殖成功率对这些发现进行了讨论，考虑了此类产卵特征和行为可能对鱼卵和幼体存活产生的潜在影响。这项工作首次对南乔治亚岛巴塔哥尼亚齿鱼的产卵动态进行了长期评估，为该物种的生态学研究以及这一具有商业重要性的物种未来的渔业管理提供了宝贵的知识。
