The Food of Post-Larval Fish. No. II (1918)

Investigation of the food of larval and post-larval fish from the townets has been continued throughout the year (1918) in the same way as previously, by examining the contents of stomach and intestine in the fresh state. From May 24th a new big net made of stramin, with a wooden frame 36 inches by...

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Bibliographic Details
Published in:Journal of the Marine Biological Association of the United Kingdom
Main Author: Lebour, Marie V.
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 1919
Subjects:
Online Access:http://dx.doi.org/10.1017/s0025315400059907
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0025315400059907
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Summary:Investigation of the food of larval and post-larval fish from the townets has been continued throughout the year (1918) in the same way as previously, by examining the contents of stomach and intestine in the fresh state. From May 24th a new big net made of stramin, with a wooden frame 36 inches by 25 inches, was used in addition to the ordinary tow-nets. Any live specimens, and these were chiefly caught in the big net, were kept in small aërated aquaria standing in running water and fed with plankton in order to see, when possible, what food they ate. In this way a few post-larval fish went through the metamorphosis into the adult form. Details of these will be found in another paper in the same number of the Journal (page 9). The tow-nettings were regularly examined by Miss Webb in order to see whether the fish were feeding on what was commonest at the moment, and this was found to be usually the case, so far as the Copepods were concerned, although most of the young fish seemed to select their food to a certain extent. In any month the Copepods which are at that time commonest in the plankton are those most eaten by the young fish, but most of them have preferences and select in various degrees. Thus in June Calanus finmarchicus and Acartia clausi were the commonest Copepods, Temora longicornis coming next, Pseudocalanus elongatus and Oithona similis not occurring so frequently. The commonest young fish in the tow-nets in the same month were the Whiting, Pollack, Rockling and Ballan Wrasse (Labrus bergylta).