of the Fishery Board for Scotland. 



91 



him in 1881 in his " Second Memorandum to the Proprietors of Salmon 

 Fisheries in the Tay District." After referring to the dual migration 

 of smolts to the sea as seemingly demonstrated by the famous Stormont- 

 field Observations, he goes on to say that "it is not confined to the 

 " first migration, but is repeated on the return of the smolts as grilse 

 "one year and as salmon the next, and on the return of the old fish 

 " after spawning — one-half coming back the following summer, and the 

 " rest not returning till the spring of the succeeding year." There 

 appears, however, to be this difference brought out by our marking, 

 that it is not from the old fish that the heavy spring salmon may alone 

 come, but that a grilse spawning, say, in the winter of 1901-02 may on 

 its first subsequent re-ascent be a spring salmon of 1903 weighing 

 18-20 lbs. Mr. Dickson, in his most interesting memorandum, regards 

 the small spring salmon as the first reappearance of the descended one 

 year old smolt. He says, further, "it is the same yearling salmon that 

 " runs all the season, beginning at 8 and 9 lbs. weight, increasing to 10 

 " and 11 lbs. in April, and ending in August at 13 and 14 lbs., gaining 

 " weight according as they make a longer stay in the salt water." But 

 with reference to the grilse, with which we are more concerned here, 

 the view advanced — if I rightly interpret it — is that the " yearling 

 salmon " may not have been in the river as a grilse, or that only a section 

 of the descended smolts return to the river as grilse. The passage 

 which seems to me to bear this meaning runs as follows : — " in regard 

 " to their return all as grilse, the first fishing for fish to be spawned 

 " opened my eyes, for, whereas I expected that the river would be found 

 " to be full of grilse, the party reported that they had not taken one 

 " between Perth and Dunkeld. If they were not in the river there was 

 " only one other place in which they could be, and that was the sea ; 

 " and this winter's fishing showed that the young salmon of the next 

 " year remained in the sea, and that the parrs, as they had divided into 

 " one and two-year-old smolts in descending to the sea, had again 

 " divided in a similar way on their return." In winter fishing our 

 experience is that grilse are about as numerous as salmon. A separate 

 note on this point will be found in Appendix VI. We have taken the 

 small class of clean-run fish during our netting operations in the winter, 

 but we have as yet no definite proof of when and where such fishes 

 pass the grilse stage. We have the grilse kelt a July salmon of 10 lbs., 

 and a next year spring salmon of 18 or 19 lbs. 



An interesting coast recapture may he noted here as bearing upon 

 the grilse to salmon stage. No. 9607 was a grilse kelt marked at Duff 

 House on the Deveron, weighing 3 lbs, on 24th March 1903. It was 

 recaptured — as has already been noted —in a bag net on the coast a 

 short distance north of Aberdeen, on 11th July 1903, weighing 6| lbs. 

 This fish on recapture was described as a clean grilse. The record is so 

 nearly a repetition of No. 6508 reported upon in my first paper, that I 

 may place the two side by side. 



6508 



f 3 lb. 

 1 5| lb. 



r ii" 



2' U 



Kelt. 



Grilse or Salmon. 



M. 



11 Mar. 1901. 

 11 July 1901. 



Deveron, Kirkton 

 Pool. 



Cove, Kincardine- 

 shire. 



9607 



| 3 lb. 

 1 6| lb. 



2' 0" 



2'' 2" 



Kelt. 



Clean Grilse. 



F. 



24 Mar. 1903. 

 11 July 1903. 



Deveron, Duff 



House. 

 Aberdeen Bay. 



