3o6 BENNET B. RAE 



On resuming full-scale fishing after the war Scottish salmon fishermen 

 began to complain even more strongly and collectively about the growing 

 menace to their fishery — a move which culminated in a request to the 

 Secretary of State for Scotland to have seal stocks reduced. Grounds for 

 complaint appear to have been confirmed by Lockley's (1954) estimate of the 

 grey seal population of the British Isles at 20,000 — an increase to from four 

 to five times the number estimated by Ritchie & Calderwood in the late 

 1920's. 



As a direct result, the wider question of seals in relation to Scottish fisheries 

 generally has been investigated during the past three years. Despite statements 

 to the contrary, a good deal is known about the food of the grey and common 

 seals, the two native British species. After weaning, both species feed for a 

 short period on crustaceans and molluscs and then turn almost entirely to 

 fish (Havinga, 1933; Fisher, 1950; Sergeant, 1951 and others). Almost every 

 fish of economic importance round the British Isles is eaten by seals, including 

 salmon, sea trout, halibut and other flat-fishes. Further evidence was obtained 

 from the examination of the stomach contents of seals killed on the Scottish 

 coast from 1958 to i960. Of sixty-four examined, forty-one were grey seals 

 and twenty-three common seals. Twenty of the grey seal and fifteen of the 

 common seal stomachs were empty, but of the twenty-one greys containing 

 recognizable food, ten were found to be feeding on salmon and five on cod. 

 Of the eight common seals, one was feeding on sea trout, one on salmon 

 parr, four on gadoids including haddock and whiting, one on mackerel and 

 two on other species. That thirty-four of the sixty-four seals were drowned 

 or killed in salmon nets may give the impression of bias towards the salmon 

 as the grey seal's main food, but in fact seals trapped and killed in nets reveal 

 a higher proportion of empty stomachs than do those shot in the sea, 

 apparently the result of the animals vomiting on fmding themselves trapped. 

 From this and other evidence the percentage of seals feeding on salmon 

 could well be higher on the sections of the coast examined. To objections 

 that the examination of stomachs of seals killed in or near salmon nets gives 

 a bias towards salmon in the results, it must also be pointed out that salmon 

 nets are fished over hundreds of miles of the Scottish Coast and that it would 

 be diflicult for various reasons, to procure a corresponding number of 

 stomach samples from areas where salmon fishing is not carried on. 



From a study of scientific papers dealing with grey seal colonies and from 

 observations on different sections of the Scottish coast it is clear that seals, 

 particularly grey seals, have been increasing in numbers in recent years 

 (Darling, 1939, 1947, 1952; Buxton & Lockley, 1947-8; Davies, 1956; 

 Eggeling, 1957; Hickling, 1958, 1959). There is ample evidence too, of the 

 harmful effect these animals are having on salmon fisheries. Briefly, this may 



