526 Scientific Proceedings, Royal Dublin Society. 



net, a tributary of tlie Foyle in tlie county Tyrone, where they do 

 great harm by rooting up the redds of larger fish, previously 

 spawned, either in order to consume the eggs and fry, or to make 

 their own redds. There can be little doubt that the fisheries, 

 would be improved if these and all other salmon remaining in the 

 river were allowed to be caught after the 15th February, at which 

 date the season might commence. On the other hand, the 

 month of October might be advantageously added on to the close 

 season, since the main body of the trout and sewin spawn during 

 that month, and are certainly not in good condition for the table. 

 After spawning is over, the kelts consume, on the average, at 

 least a dozen fry per diem, almost all of which are young salmon 

 and sewin, which are then dropping down the river. Granting 

 that but one-half of these are salmon -smolts, every kelt which 

 remains in the river for one hundred days after February 15th — 

 not an inordinate assumption — consumes six hundred salmon-fry ; 

 reducing this number again by one-half, to allow for losses which 

 might have occurred from other causes during the perils of migra- 

 tion, we arrive at a dead loss to the fishery of three hundred grilse, 

 which, on their return in a few months, would have weighed 

 about 1000 lbs. : against which we have only a single kelt, which, 

 if it should have chanced to escape the dangers of the sea, would 

 have returned the larger by 4 lbs. or 5 lbs. During the summer of 

 1875 I took from The Bush, county Antrim, a grilse of about 4 lbs., 

 which was so completely covered with fungus that on the fins and 

 part of the head alone was the skin visible ; this fish was fresh- run, 

 and taken not a mile from the sea. The following fact seems to 

 prove that salmon do not invariably breed annually : — 'In January, 

 1878, numbers of salmon were seen, and one actually captured 

 with a gaff, leaping and sporting on the surface, about five miles 

 out to sea off Portrush, county Antrim. The captured fish proved 

 to be in perfect condition, showed no signs of breeding, and 

 could not therefore have intended so doing that winter. This, and 

 presumably those in company with it, were Foyle fish, which are 

 easily distinguished from those which ascend the Bann. The 

 large salmon, too, which run up our rivers early in spring, could 

 hardly have spawned during the preceding winter and so quickly 

 have recovered their condition. It is probable that local, or even 

 individual causes, which may be either temporary or persistent. 



