SUMMARY AND GENERAL REPORT. 



The present report, like that of last year, deals mainly with 

 the investigations relating to the herrings. 



Our previous investigations referred for the most part to 

 the Northumberland shoals and the trawled herrings of the 

 Dogger Bank region. Last year we found that the Northum- 

 berland herring was related to the Firth of Forth spring spawn- 

 ing shoals. On approaching the ^vork, which is the subject of 

 the present report, we thought it desirable therefore to obtain 

 samples from a much wider area, and we are now dealing with 

 the results of the examination of material from Stornoway, 

 Lerwick and other ports along the East Coast to Yarmouth. 

 Altogether, the number of herring investigated with respect to 

 size, age, degree of development and growth amounted to 6,848. 



Over the greater part of this wide area we found that the 

 summer shoals were young fish, the greater number of them 

 with three winter rings, and thus similar to the summer herrings 

 of Northumberland. The shoals to the east of the Shetlands 

 differed in that they did not contain so many young fish. In 

 autumn the grounds frequented by the young fish were invaded 

 by spawning shoals of older fish, and it was interesting to note 

 that these spawning assemblages included such of the summer 

 fish as had become mature. The winter shoals consisted of 

 older fish with six and seven rings as a rule, but presented a 

 scarcity of herrings with five winter rings. 



AVith regard to maturity a wide variation was exhibited. 

 Virgin fish at stage I. were found with six winter rings in 

 summer shoals, and spawning fish with two winter rings in 

 both autumn and spring shoals. Early maturity accompanies 

 rapid growth in length. From a consideration of the growth 

 made up to the formation of the first winter ring it has been 

 concluded that the summer shoals of comparatively young 

 herring are the products of both spring and autumn spawmers, 

 and the same data has lead to the opinion being expressed by 



