Stock Fluctuations throughout Reproduction and Recruitment Process of the Japanese Common Squid, Todarodes pacificus, related to Climate Changes

与气候变化相关的日本鱿鱼 (Todarodes pacificus) 繁殖和补充过程中的种群波动

• 批准号: 12460080
• 负责人: SAKURAI Yasunori
• 金额: $ 7.3万
• 依托单位: HOKKAIDO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12460080/
• 关键词: Todarodes pacificus; Stock Fluctuation; Climate Change; Gelatinous Egg Mass; Mixed Layer Depth; Marine Environment; Reproduction and Recruitment; Survival of Paralarvae; 混合層深度; 冬季季節風; アリューシャン低気圧; ふ化幼生の生残; Todarodes pacificus; Stock Fluctuation; Climate Change; Gelatinous Egg Mass; Mixed Layer Depth; Marine Environment; Reproduction and Recruitment; Survival of Paralarvae; 混合層深度; 冬季季節風; アリューシャン低気圧; ふ化幼生の生残

In short-lived squids, recruitment success most likely depends on the physical and biological environments at the spawning and nursery grounds. No egg masses have been observed in the natural habitat. During 2000-2002, MOCNESS and an ROV were used to examine the distribution of egg masses and paralarvae of Todarodes pacificus in the Sea of Japan. Gelatinous egg masses were observed at two stations in the Tsushima Current along the continental shelf off the Oki Islands in November, 2000. They occurred within the pycnocline (75 and 95 m depth, respectively), where temperatures were about 18℃, which was suitable for embryonic development. Upon hatching, paralarvae may rise to the surface layer, where they would be carried into the convergent frontal zone in the Tsushima Current.Annual catches of T. pacificus, have markedly increased since the late 1980s, and recent catches have equaled those of the 1960s. The winter spawning area of T. pacificus in the East China Sea shrank when adult stocks decreased during a cool regime that occurred before 1988, and that its fall and winter spawning areas extended and overlapped in the Sea of Japan and East China Sea when adult stocks increased during a warm regime after 1989. Successful hatching from egg masses was to be higher when the mixed layer depth (MLD)is shallower than the bottom depth. We examined the relationship between annual catch of the winter-spawning stock, and wind speed and air temperature in the East China Sea in February during 1980-2000 to determine how a series of calm and warm winters might promote a stock increase related to changes in the MLD. Annual catches markedly increased during a decade of weak wind speed and warm air temperature from the mid-1980s to mid-1990s, suggesting that the strength of winter wind stress affects the winter-spawning stock fluctuations in T. pacificus.

在短暂的鱿鱼中，招募成功很可能取决于产卵和托儿所的物理和生物环境。在自然栖息地中未观察到卵子。在2000 - 2002年期间，使用MOCNESS和ROV检查日本海洋海洋太平洋的卵子和副群的分布。在2000年11月，在oki群岛的连续架子上观察到在Tsushima电流的两个站点观察到凝胶状卵，它们发生在Pycnocline内（分别为75 m和95 m的深度），温度约为18°，适合于胚胎发育。孵化后，副群可能会上升到表面层，在那里它们将被带入Tsushima电流的收敛额叶区域。太平洋T. Pacificus的捕捞量已经显着增加，自1980年代后期以来，最近的捕获量等于1960年代。 T的冬季产卵区。当成年股票在1988年之前发生的凉爽状态下减少时，东中国海洋的太平洋萎缩，秋季和冬季产卵区域在1989年以后的温暖孵化过程中延伸并重叠在日本和东中国海中。从鸡蛋中成功孵化时，当混合层深度（mld）是鸡蛋（MLD）比最低的深度时，从鸡蛋中孵出的孵化量会更高。我们研究了1980 - 2000年2月的冬季产量库存的年度捕获与东中国海的风速和空气温度之间的关系，以确定一系列平静和温暖的冬季如何促进与MLD变化有关的股票增加。从1980年代中期到1990年代中期，在十年的风速和温暖的空气温度中，每年捕获的强度显着增加，这表明冬季风应力的强度会影响太平洋T. Pacificus的冬季产量波动。