浮游深度によるマイワシ卵の発生速度の相違について

概要

論文の詳細を見る
Simultaneous horizontal haulings of several different depths were made on the sardine spawning ground off Noto Peninsula, Japan Sea, in the spring of 1955. Observations on the plankton samples obtained have led to the following. Of the sardine eggs belonging to the same age category, those eggs floating in the upper layers are more advanced in development than those in the deeper layers(Table 1). This phenomenon is inconsistent with the view that in sea waters the pelagic sardine eggs would be continuously mingled to a great extent by large-scale eddy turbulences and their floating depths would be disturbed incessantly and irregularly. On the other hand it is supposed that they would for some reasons be kept rather unchanged in their relative positions to each other during the embryonic development and that based upon the vertical gradient in water temperature in the sea(Fig. 1), the above-mentioned difference by depths in the rate of development would result.
日本生態学会の論文
1957-08-31