On the periodic occurrence of the principal food-fishes in the North Sea and Skagerrak, based on the returns of German fishing steamers

Appendix F of Rapports et Proces-Verbaux des Reunions Vol. 3.

If, in response to the invitation of the Bureau of the International Council for the study of the sea I give here some observations on the periodic occurrence of the principal fishes, based on the rich statistical material of the “Deutsche Seefischerei Verein”, I am nevertheless well-aware, that in so doing, I am raising an old and a difficult problem. It has been well-known for long, that most of the fisheries are carried on at certain periods and that the existence of such periods is almost always conditioned by the habits of the fishes. If the fish occur in quantities worth catching, the fishermen as a rule are soon on the spot and do not move until the catches no longer repay the costs of the time and labour. Thus arises a fishery-period