of the. Fishery Board for Scotland. 



135 



who took part in thq discussion on Dr Day's paper on ' The Food of 

 ' Fishes,'"^ it appears that the cod restricts itself almost entirely to one 

 kind of food during the time that it remains on some of the large fishing 

 banks ofip the American and Norwegian coasts. 



Thus, for instance, during the Labrador fishing, the cod feed almost 

 entirely on capelin {Mallotus villosus) ; a similar state of things is 

 found on the coast of Norway. When on the great banks, the cod feeds 

 almost entirely on the immense shoals of herring collected there. In the 

 winter fishing off the New England coast clams are used as bait, because 

 the cod are then known to be feeding at the bottom, and a molluscan diet 

 is found to be the most acceptable. Such observations undoubtedly point 

 to the conclusion that the migrations of the cod are to a large extent 

 dependent on the proper supply of food. It further appears that a par- 

 ticular class of food which may be much in demand at one season of the 

 year is not at all sought after at another ; in other words, that the cod in 

 its migrations not only changes its food through necessity, but that it 

 shows a preference for this change. How far the migrations may be 

 brought about by a desire for a change of diet is a question which at the 

 present cannot receive a satisfactory answer. In connection with this 

 subject an interesting observation has been reported by the Fishery officer 

 at Anstruther. It is well known that herring forms, at certain seasons at 

 least, a very important part of the food of the cod and other fishes. On 

 this account herring are used as bait in many fish centres whenever they 

 are procurable. Yet it appears from Mr Mair's account that, in spite of 

 an abundance of herring, the cod may seek other food. The following is 

 an extract from Mr Mair's letter, dated July 31, 1885 : — * Herring were 

 ' plentiful on the distant cod-fishing ground in spring and summer during 

 ' the period of the cod fishing, but herring were rarely met with in the 

 ^ cods' stomachs ; and any stray herring found were most likely the bait by 

 ' which the fish had been caught. Towards the end of the cod-fishing 

 ' season, however, I was informed by one curer of a cod's stomach with 31 



* herring in it ; and another curer had met with one containing 27 herrings. 



* These were exceptional cases.' On the other hand, on the West Coast the 

 cod appears to have been feeding principally on herring during a part at 

 least of this time. On the 8th of April 1885 Mr Wilson, Fishery officer 

 at Girvan, sent in the following report : — ' From the 1st January to the 

 ' 26th March all the stomachs of cod (and saithe) examined contained from 



* 5 to 8, 10, and up to 17 herrings. From 26th March to 1st April the 



* stomachs contained principally herring spawn. From 3rd to 6th of April 

 ' some of the stomachs contained cray and shell fish ; but most were empty. 

 ' On the 7th and 8th of April the stomachs were altogether empty. 



* Herring appear to have left the ground about the 26th March ; the cod 

 ' then fed on herring spawn. After the 1st April the spawn must have 

 ' quickened and floated, as none was found in the stomach of the cod, which 

 ' then fed on ground shellfish.' In reference to the absence of food in the 

 stomachs of the cod on the west coast after the beginning of April, it 

 should be noted that in this district the cod themselves spawn about this 

 time ; and it is usual for the fish to refuse food during the spawning- 

 season. During the winter codfishery in the Anstruther district, herring 

 form a considerable part of the fish's food 



With these exceptions^ we have not had any evidence yet brought 

 under our notice to show that around the Scotch coast the cod does not at 

 all times partake of a most varied diet. The following table shows the 

 classified contents of between two and three hundred stomachs : — 



* Conferences held in connection with the International Fisheries Exhibition, 

 London, 1883. Pt. III. 



