of the Fishery Board for Scotland. 



97 



inferior species, the Humpback, has been successfuly introduced. This 

 Humpback (Oncorhynchus gorbuscha) was rather despised in earlier days in 

 the Fraser Kiver, but as the best species seem to decline from sheer over- 

 fishing, and especially from overfishing on the part of American fishermen, 

 the affect of whose operations touch British Columbia, the less important 

 species are canned to a greater extent than formerly. 



Glancing again at the opposite side of this question, I would note the 

 failure, previously described in the Twenty-ninth Annual Report (p. 247), of 

 operations at M 'Harry Inlet, Alaska, when for a period of 17 years hatching 

 was carried on in order to increase the run of " red salmon " * at the ex- 

 pense of humpbacks and dog salmon. The upshot was that, in spite of 

 extensive hatching, and the barring of the two undesired species to the 

 upper waters, the red salmon never become more numerous or the others 

 less so. 



When, before the war, it was possible in Scotland to carry on a certain 

 amount of experimental work, I had hopes, as the Board are aware, of mak- 

 ing a test of the actual return of artificially hatched salmon, in a West 

 Coast river, the intention being to rear to the smolt stage and systematically 

 mark the young fish, and to ascertain as far as the admirable conditions 

 kindly offered would allow, the entire stock of fish, including the marked 

 fish which returned to the river over a series of years. This had to be 

 abandoned unfortunately. 



The one instance we have in Scotland of definite proof of a return from 

 artificial hatching is the result of the Glen Etive operations by Mr. Ian 

 Nelson, already published as a separate paper, Fisheries Scotland, Salmon 

 Fish., 1914, /. (October 1914). From 40,000 salmon fry turned out in 1909 

 plus 1000 yearlings in 1910, 11 grilse were obtained in 1912, and 5 four 

 year old salmon in 1913. 



Of wild smolts marked when going to sea we may recollect the 5500 

 marked in the Tay by Mr. M'Nicol, and the return of 110 fish spread over 

 a period of 4 years, viz. 43, 57, 8, and 2, which is equal to about 22 per 

 1000. 



We have certainly had no adequate test of the relative returns of wild 

 and artificially hatched smolts. If fry are liberated rather than smolts, it 

 may be that the remnant become as capable of taking care of themselves 

 as wild smolts, but the largest hatchery yet attempted with us — that of 

 the Duke of Eichmond and Gordon at Fochabers — has treated only a 

 million eggs, while a varying number of the fry have been reared to the 

 smolt stage. After 25 years' experience, this hatchery has recently been 

 given up for want of any proof of a definite kind that benefit has resulted 

 to the Kiver Spey. 



It may be that instead of one million, three or five millions should have 

 been hatched so as to secure successful results. In any case, the chances 

 of success would have been greater, or the results at least more obvious, but 

 I confess to being brought up against the consideration whether or not in a 

 hundred mile river of spawning beds like those of the Spey, with an in- 

 creasing stock of fish, the continuance of artificial hatching on any scale is 

 in any way necessary. 



Further, the question may very fairly be asked with reference to Scot- 

 land in general, is a return of from 3 to 5 adult fish per thousand fry 

 turned out really worth while, except in rivers where it is clear that natural 

 spawning must certainly be most limited, as for instance in the Kirkaig or 

 Morar, or where the redds are subject to exceptional danger from floods. 



It is clear, I think, that if salmon hatching is extended, it should be 



* The Sockeye of Fraser River and Puget Sound, Bureau of Fisheries. Document 

 No. 730. 



7 



