SALMON— ASCENDING RTVETIS. 



71 



from the observation of Mr. Willis-Bund, made in llie .Severn, and Mr. Ander.son 

 in the Forth, and ^Mr. Russcl in the Tweed, -whieh are recorded below. From 

 these it is ajiparent that, contrary to the movements of the adult salmon, the grilse 

 or young tish may bo said to ascend all at once, commencing about Juno, doubt- 

 less owing to their having then attained sufficient strength for the purpose. Tho 

 later in the year these grilse ascend the larger (comparatively) they are. Young 

 fish, as has been pointed out by Russcl, arc apt to live in shoals, and if \vc refer 

 to his table respecting Salmonida3 in the Tweed, we see that the trout suddenly 

 increase in numbers in June, but decrease in proportional weight, owing to tho 

 ascent of young fish. 



Heavy rains occasioning floods may not only increase the take in the rivers and 



first -were recorded on June 28th, and in 1882, a week later. (5) The second run of gi-ilse ascends 

 about the middle of June, or during the second spring tide ; they arc from '.i lb. to 5 lb. (G) The 

 " autunm sahuon " ascend at the end of June ; are from IG lb. to 40 lb. (7) Witli tlic first spring 

 tide in July, quantities of grilse ascend. (8) With the first spring tide in August, grilse from 81b. 

 to 16 lbs. ascend in shoals, and many are heavy in spawn. (9) " Tlie gray scluilc sahnon," or tho 

 regular breeders, ascend witli the first spring tide in September, or later if the water is low. 

 Many are from 20 lb. to 50 lb. ; some are very dark, others very red. (10) There is also the 

 " gray schule grilse ; " the most are ugly-looking fish, and very shiny all over their scales. 



Eussel (TIic SahiioH, 1864) remarked that the reason salmon ascend rivers more or less every 

 month of the year, while grilse only do so at certain periods, or so to speak come all at once, must 

 be owing to one being an adult form capable of ascending at any time, while the other is a young 

 fish which tirst attains to that capacity at that season when its ascent is practically bound to 

 begin. The following return shows the proportions of salmon, grilse, and trout to every 1000 of 

 each kind caught on an average of years in the net fisheries of the river Tweed : — 



Salmon. GEHiSE. Trout. 



Salmon ascend in every month of the year, in numbers comparatively not very unequal. 

 Grilse, speaking roundly, do not ascend in the first half of the year, and all but a fraction within 

 two consecutive months in the middle of the year ; subsequently, their ascent is checked. Forms 

 ascending throughout the year being adults ; those coming in shoals being the young of the 

 same species. That this is so is further borne out by the trout column, wherein are comprised 

 both old and young, and in June they suddenly increase by 300 per cent., and another 50 per cent, 

 in July, during which month a fourth of the whole of the year's captures were recorded, while the 

 average weight falls off during the months when the young appear to be ascending. The increase 

 of trout in October is due to fish ascending to spawn, when the average weight of the fish 

 increases. Eussel has also shown that in examining some returns of takes of grilse and salmon 

 from the Tweed, he found that the proportion which the grilse of any one year bore to the average 

 number of grilse, was found to be just about the proportion which the salmon of the following 

 year bore to the average number of salmon. Taking a series of years, the average weight of grilse 

 captured in the Tweed was found to be in June, 3 lb. llj oz.; July, 4 lb. 5| oz. ; August, 

 4 lb. 15 oz. ; September, 5 lb. 12^ oz. ; October, 6 lb. llf oz. : the late comers having been 

 longest in the sea. 



The following are the figures supplied me at luveran on the Shin by Mr. Mackay, and which 

 include the takes by anglers for the four years ending 188G in that river : — 



S.VLMON. Grilse. 



Dr. Frie came to the following conclusions respecting the migrations of the Bavarian salmon 

 (he omits the grilse), among which he observed three distinct times of ascent from the sea. A. 

 Not read]) for upaivning when ascending : (1) At the end of February under the ice, or March until 

 May. Large and strong fish from 25 lb. to 50 lb. (avoirdupois), famous as " violet salmon." 

 (2) From the middle of June till August, if the rivers are not too low. From 12J lb. to 22 J lb. 

 Flesh reddish, and known as " rose salmon." B. Eeadij to spaicn on arrival : (3) First half of 

 September until the end of November, and in mild winters until December. Weak fish from 

 3 lb. to 10 lb., or even 15 lb. Flesh pale, and known as "silver salmon" {U.S. Fishery 

 Reports, 1876, p. 607). 



