22g DISCOVERY REPORTS 



My own experience of trawling in the southern hemisphere has been hmited to a few experimental 

 hauls off the Falkland Islands and off the south-west coast of Africa, but I have seen enough to recognize 

 the tremendous amount of hard work in the field that these trawling surveys must have entailed. This 

 is especially true of the last and most comprehensive of the surveys, when Mr Gunther was in charge 

 of the scientific work and had as his assistant Mr (now Comdr) G. W. Rayner. I think this survey 

 was one of the most arduous pieces of field-work ever completed by the Discovery Investigations ; 

 and, as my two colleagues were always anxious to point out, its success was largely due to the able 

 and willing co-operation of the Captain, net-man and ship's company. 



The work of writing up the report has been carried out in the Laboratory of the Marine Biological 

 Association at Plymouth, by courtesy of the Director, the late Dr S. W. Kemp, F.R.S., who, while 

 Director of Research to the Discovery Investigations, planned much of the work here described. 

 Dr Kemp's personal kindness and encouragement have helped me throughout my working life, and I 

 am sure all members of the Discovery scientific staff would wish to say the same. I have gained 

 much from the advice and encouragement of the staff of the Laboratory and more especially from 

 hints on the handling of numerical data by Mr E. Ford and Mr G. M. Spooner. Had these two 

 gentlemen not been away on war service during most of the period my task would have been lighter. 

 The rapidity with which the librarian, Miss M. Sexton, procured obscure references under all the 

 difficulties of wartime conditions was a great help. I have gained much from an all-too-brief interview 

 with Mr C. F. Hickling of the Ministry of Agriculture and Fisheries (now Fisheries Advisor to the 

 Colonial Office), who also helped with the loan of some of his important papers on Hake. This brings 

 me to a point that needs emphasis if the work described here is to be justly appreciated — it was planned 

 and carried out before the results of the last decade of fishery research, prior to the war, were known. 

 If, for example, the final results of Hickling's prolonged work on European Hake had been available 

 there is no doubt that our programme could have been modified with advantage, but our data were 

 collected before Hickling's work was complete. 



FIELD METHODS AND PRELIMINARY OBSERVATIONS 



The three trawling surveys were carried out by the R.R.S. 'William Scoresby' in autumn (March- 

 April) 1927, winter (June-July) 1928, and throughout the whole of the warmer half of the year 1931-2 

 (October-April). A few additional observations were made within the area by the R.R.S. ' Discovery' 

 and by the R.R.S. ' Discovery II '. A description of the ship and of the gear will be found in Kemp, 

 Hardy and Mackintosh (1929). In the more detailed parts of this report abbreviated descriptions of 

 the gear have been used, as standardized throughout the station lists in Discovery Reports. Meanings 

 of the abbreviations relevant to the present work are repeated here for the convenience of the reader. 



For this study of the bionomics of the fish fauna, the gear may be grouped under two main headings : 

 ' Trawl -|- accessory nets' and 'Other gear'. 



' Trawl + accessory nets ' comprises : 



OTC Commercial otter trawl, 80 ft. headline, 3 in. cod-end mesh. 



N7-T Net 7 mm. meshl Fine-meshed nets attached to the back of 



N4-T Net 4 mm. mesh ,- the trawl as described in the work men- 



NCS-T Coarse silk net J tioned above. 



' Other gear' includes a motley collection of apparatus that helped to extend our knowledge of the 

 distribution of the fish fauna in lesser ways. (The finer plankton nets, which scarcely ever catch fish 

 except in their larval stages, and hydrological apparatus are not considered here.) 



