During the years 1930–9 a series of records was obtained on the abundance of pelagic young of teleostean fish occurring in standard half-hour oblique hauls made with the 2 m. stramin ringtrawl in the neighbourhood of the Eddystone. These results provided a record by which the composition of the young fish populations could be compared from year to year and any marked changes brought to notice. During the course of the observations there had been a striking reduction in abundance of young fish, and this had been correlated with the movements of water masses as indicated by certain plankton animals. The series of observations was brought to a conclusion in August 1939 on the outbreak of war. The earliest opportunity after the cessation of hostilities has been taken to continue these observations on young fish, and collecting was started in June 1946 when a research ship was once more available. There has thus been a gap of nearly seven years during which there has been no detailed information on the conditions in the waters off Plymouth. The 1946 collections were started too late to include the main period of abundance of young fish resulting from the spring spawners, but they afford evidence that as regards the summer spawners at any rate there is no significant change from the conditions existing in 1939. We cannot say what the conditions have been during the intervening years, but analyses of phosphorus content of the water during each of the winters in the period 1939–46 tend to show that conditions have remained much as they are at present, and that it is unlikely that there has been any large incursion of the rich water characterized by Sagitta elegans which supports a large population of young fish.

中文翻译：

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关于幼鱼的季节性丰度。八。1946 年，六月至十二月

在 1930-9 年期间，在用 2 m 进行的标准半小时倾斜拖运中，获得了有关硬骨鱼类远洋幼鱼丰度的一系列记录。在 Eddystone 附近的 stramin ringtrawl。这些结果提供了一个记录，通过该记录可以逐年比较幼鱼种群的组成，并注意到任何显着的变化。在观察过程中，幼鱼数量显着减少，这与某些浮游动物所表明的水团运动有关。这一系列观察在 1939 年 8 月战争爆发时得出结论。在敌对行动停止后最早的机会已被用来继续对幼鱼进行这些观察，1946 年 6 月，当一艘研究船再次可用时，开始收集。因此，在将近七年的时间里，没有关于普利茅斯附近水域状况的详细信息。1946 年的收集开始得太晚，无法包括春季产卵鱼产生的幼鱼丰足的主要时期，但它们提供的证据表明，就夏季产卵鱼而言，无论如何与 1939 年的情况相比没有显着变化。我们不能说明在此期间的情况如何，但对 1939-46 年期间每个冬季的水中磷含量的分析往往表明情况与现在一样，而且不太可能富水曾发生过大规模入侵，其特点是箭矢线虫这支持了大量的幼鱼。