F. DAY: PERIODS OF MIGRATION. 



I23 



There is hardly a month in the year when fresh-run salmon may 

 not be found in our rivers,* but the main run for spawning purposes 

 occurs as a rule from October to January, or even later. Some of 

 the December and January fish, however, are in that condition, as I 

 have shown, that they could not spawn for many months to come , 

 and I am disposed to think that it is only autumn and winter 

 ascending ones that breed, but experiments are much needed to test 

 this. I now propose adverting to such facts as have been recorded 

 respecting the various runs of salmon which ascend our rivers. 



Mr. Willis-Bund, in his account of the Severn ('Salmon Problems'), 

 shows at least eight distinct runs during the year. They may be 

 summarised as follows : — End of December or January, the 

 largest run of the season, and spawning fish. (2) End of January 

 or February, or later ; spawning fish fewer in number, but generally 

 large in size. (3) A run in February of large clean fish, but at the 

 end of the month of gillings.t (4) February and March, a spring 

 run of gillings, which press up to the head-waters of the river, and 

 are the early spawners for the next season. (5) A small run of 

 grilse, and some small salmon, during April. (6) June and July, the 

 main run of grilse. (7) Autumn run of Michaelmas gillings. 

 (8) Great run of spawning fish, in October and November. But it 

 must be noted that all of the foregoing do not take place invariably 

 every year — thus grilse or gillings may be absent ; but there are, as a 

 rule, three distinct runs of spawning fish, and five runs of clean fish, 

 and, irrespective of the foregoing, there are individuals moving about. 

 Fish which are ascending alone do not appear to be so eager to press 

 up, but stop at the foot of weirs in the pools ; while the largest run 

 of salmon is on a spring tide. Possibly male fish pass up sooner 

 than do the females, for at certain times in the Usk the higher up the 



* 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 ready for spawning when ascending: (1) At 

 the end of February under the ice, or March until May. Large and strong fish 

 from 25 lbs. to 50 lbs. (avoirdupois), famous as 'violet salmon.' (2) From the 

 middle of June till August, if the rivers are not too low. From 12% lbs. to 

 22% lbs. Flesh reddish, and known as 'rose salmon.' B. Ready to spawn 011 

 arrival : (3) First half of September until the end of November, and in mild 

 winters until December. Weak fish from 3 lbs. to 10 lbs., or even 15 lbs. Flesh 

 pale, and known as 'silver salmon' (U.S. Fishery Reports, 1876, p. 607). 



f ' Gillings ' is a local term for salmon from 8 lbs. to 15 lbs. weight, or after it 

 has ceased to be considered a grilse, and fish of this size are supposed to be in their 

 second breeding year, and to migrate together, and not along with other salmon, 

 while grilse or botchers are fish up to 8 lbs. weight. 

 April 1886. 



