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首页> 外文期刊>Journal of Northwest Atlantic Fishery Science >Larval Abundance and Mortality of Atlantic Herring (Clupea harengus L.) Spawned in the Georges Bank and Nantucket Shoals Areas, 1971-78 Seasons, in Relation to Spawning Stock Size
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Larval Abundance and Mortality of Atlantic Herring (Clupea harengus L.) Spawned in the Georges Bank and Nantucket Shoals Areas, 1971-78 Seasons, in Relation to Spawning Stock Size

机译：1971-78季节在乔治银行和楠塔基特浅滩地区产的大西洋鲱鱼的幼虫丰度和死亡率，与产鱼量有关

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摘要

Time of hatching, abundance of recently-hatched larvae and their relative contribution from the Georges Bank and Nantucket Shoals spawning grounds, as well as mortality during the autumn-winter period are estimated for eight spawning seasons on the basis of data from the ICNAF Larval Herring Surveys which were conducted during 1971 78. Indices show that the highest initial larval production occurred in 1973 and 1974 as a result of the large 1970 year-class and that there was a decline in production of about two orders of magnitude by 1976 and thereafter. The collapse of the fishery on Georges Bank in 1976 coincided with a delay in peak spawning from mid- to late October, a contraction of the spawning season, and a shift of the remaining spawning population to northwestern Georges Bank and Nantucket Shoals. Furthermore, the mean seasonal mortality rate of 5% per day, estimated over the first 6 months of life, varied significantly (3-7%/day) after the 1975 season. The initial larval production estimates are compared with abundance indices (age 3+ herring) from spring bottom-trawl surveys, and sources of bias are evaluated
机译：根据ICNAF幼虫鲱鱼的数据，估计了八个孵化季节的孵化时间，最近孵化的幼虫的数量及其在乔治银行和楠塔基特浅滩产卵场的相对贡献以及秋冬季的死亡率。 1971年进行的调查78.指数显示，由于1970年的等级很高，最初的幼体产量出现在1973和1974年，到1976年及其后，产量下降了大约两个数量级。 1976年Georges Bank渔业的崩溃与10月中旬至10月下旬高峰产卵的延迟，产卵季节的缩减以及剩余产卵种群向西北Georges Bank和Nantucket Shoals的转移相吻合。此外，1975年季节之后，在生命的头6个月估计每天的平均季节性死亡率为5％，差异很大（3-7％/天）。将初始幼虫产量估算值与春季底拖网调查的丰度指数（3岁以上鲱鱼）进行比较，并评估偏差来源

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