FISHING AT HOME AND ABROAD 

 Shortly previous to the marking operations Mr H. W. Johnston was 

 conducting an independent series of observations higher up the Tay. He 

 first succeeded in establishing the fact that the age of a salmon, its periods 

 of feasting in the sea, of fasting in fresh water, and its act of repro- 

 duction, are all registered by a series of rings and lines formed upon the 

 scales as they grow. The exposed part of the scale is almost featureless; 

 the lines of growth are revealed by the microscope only upon that part of 

 the scale — about two-thirds — ^which is embedded in the skin. Mr Johnston 

 co-operated with Messrs Calderwood and Malloch in watching the result 

 of marking smolts; since then research has been carried on in the Wye 

 by Mr J. A. Hutton, in the Severn by Mr Willis Bund, and in Norway 

 by Herr Knut Dahl, while Miss Philippa Esdaile, of Manchester University, 

 has published some extremely useful results of her examination of scales 

 from various rivers. While it may be taken as certain that the growth and 

 vicissitudes of a salmon do leave a record upon its scales, it would be pre- 

 mature to announce a definite and final interpretation of that record. 

 Some of those engaged in investigating the matter have been bolder than 

 others in arriving at a conclusion; until a more perfect agreement has been 

 come to, it may be well to hold judgment in suspense, for this is a problem 

 which can only be solved by observation upon an extended base of opera- 

 tions.* 



The toughest morsel for the ordinary angler and the professional fisher- 

 man to digest is the inference that a salmon bearing no spawning mark on 

 its scales must of necessity be a maiden. It has been suggested that this 

 mark is caused by the crushing together of the scale margins when the 

 body of the fish contracts after spawning. Mr Calderwood has ascertained 

 that a female salmon parts with twenty -three per cent of her weight in the 

 act of spawning and Mr Johnston calculates that a spring salmon of 18 lb., 

 measuring 18| in. in girth, will shrink to 14^ in. in girth after spawning, 

 its length remaining the same — ^viz., 14^ in. As the number of scales remain 

 the same before and after spawning, it is easy to understand that they 

 get crushed together when the periphery of the fish is diminished so con- 

 siderably; but it requires further investigation to establish the fact that 

 spawning cannot take place without leaving its mark upon the scales. 



*The chief literature on the subject consists of Mr H. W. Johnston's papers in the 23rd and 25th A HHual Reports 

 of the Fishery Board for Scotland (Part ii, Appendix 2 in each volume) ; The Life of the Salmon, by W. L. Calderwood, 

 1907; Life-Hiaory and Habits of the Salmon, by P. D. Malloch, 1910; The Age and Growth of Salmon, by Knut Dahl, 

 translated into English and published by the Salmon and Trout Association, Fishmongers' Hall, 1911, and a paper by 

 Miss Philippa Esdaile, reprinted from the Proceedings of the Manchester Philosophical Society, 36 George Street, 

 Manchester, 1912. 



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