POPULATION DYNAMICS OF THE ATLANTIC HERRING 9 



(i) A rapid redevelopment of the German trawl fishery for adult herring to 

 reach landings of over 300,000 tons in 1955. 



(2) A striking decline in landings from the British drift net fisheries to less 

 than 100,000 tons in 1955. 



(3) The expansion of travel fisheries for adult herring based on other European 

 countries besides Germany, notably from Sweden, the Netherlands, Belgium, 

 France and, more recently, Poland. 



(4) A further extension of the regions fished in both the northern and southern 

 North Sea. In particular, an intensive trawl fishery for herring developed 

 after 1952 on the Southern Bight spawning grounds off the Belgian and 

 French coasts (Fig. 3). 



(5) An overall rise in total landings from these 'adult' fisheries to over 700,000 

 tons in the period 1952-5, which was rather more than the highest recorded 

 landings in the earlier periods. In this period, however, the discarded portion 

 of the catch was very small, so it is likely that the peak annual catches of 

 adult herring in this period were about the same as in the earlier periods. 



In addition to these developments, an intensive fishery for adolescent 'pre- 

 recruit' herring (fish mostly less than two years of age), for industrial purposes, 

 developed after 1950 from Denmark and Germany on the 'nursery ground' 

 (Bloden) to the south and east of the Dogger Bank (Figs. 2 and 3). The land- 

 ings from this fishery rose from about 5,000 tons in 1950 to over 100,000 tons 

 in 1955* or to approximately one-seventh of the total North Sea 'adult' 

 herring catch. 



It is evident, therefore, that in the years since 1920 extensive changes have 

 taken place in the nature of the North Sea herring fisheries. The trawl has 

 superseded the drift net as the principal method of capture; the fisheries have 

 extended their range in time and space; the herring have become exploited 

 from a younger age, and the contributions to the total catch, by the par- 

 ticipating countries, has changed substantially. It is in the hght of these 

 complex fishery events that the decline in the British drift net fisheries must 

 be viewed. 



DECLINE OF THE BRITISH DRIFT NET FISHERIES 



Throughout this period of change the British fisheries in the north-western 

 North Sea in summer and off the East Anghan coast in autumn remained 

 traditional drift net fisheries for good quahty herring for human consump- 

 tion (the trawl fisheries for herring from the Humber and Scottish ports had 

 ceased completely by 1952). As shown in Fig. 2, their combined landings 

 dropped from an average level of about 450,000 tons in the years up to 1914, 



* These figures are not included in the 'total' North Sea landings in Fig. 2, Those refer only to 

 the 'adult' herring fisheries. 



