DISCUSSION 



J. B. Cragg: If seals take an amount of salmon equivalent to one-quarter 

 of the total catch, would this be available to the fishery were the seals 

 removed? 



K. A. Pyehnch (Speaking for B. B. Rae): Rae does not suggest this: 

 his point is that the presence of the seals makes the fishermen work harder 

 for what they take. 



J. B. Cragg: But isn't it true that although the seal population is rising, 

 the salmon catch is rising in parallel? 



K. A. Pyefinch: No marked trend in salmon catch is detectable. 



J. C. CouLSON : Records go back 1 50 years of complaints by fishermen 

 of seal damage to salmon, and there is no evidence that this is a recent 

 problem, nor that the recent rise in seal population is as spectacular as has 

 been asserted. Many remote Scottish beaches were omitted from early 

 surveys and two different census methods have been used. One was a direct 

 count of the total number of seals visible and the other a count of the calves 

 and a subsequent multiphcation by an arbitrary figure of four. Lockley used 

 the latter procedure: it is possible that the 1929 census was based on a direct 

 count. 



I. A. McLaren: Based on a 1916 total of 400 animals a population rise 

 to 1,500 by 1929 would be reasonable, but 4,000 unlikely. 



E. A. Smith : A great amount of fish of economic importance must be 

 caught away from inshore waters. But to date no analyses have been made 

 of the stomach contents of pelagic grey seals. Therefore Rae's estimate that 

 seals consume one fifth to one quarter of Man's annual catch is based on 

 inshore seals only and is not representative. 



Secondly, Lockley's figure of 20,000 seals was arrived at in 1954 — six 

 years ago. No one had been to North Rona — the 'headquarters' of the 

 species in Britain — since Fraser Darling's 1938 visit, and no counting had 

 been carried out in the Orkneys. Lockley's figure is consequently unreal and 

 likely to be an imderestimate. 



Thirdly, we have been told that common seals consume an average of 

 II lb offish per day, and grey seals 15 lb. I suggest that we have no such 

 information. 



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