BULLETIN OF THE UNITED STATES FISH COMMISSION. 429 



86 NOTES OIV THE BIOLOGY OF THE HAI.IWOIN ANO GRILSE. 



By JOHN ANDERSON. 



[From a letter to Prof. S. F. Baircl.] 



I have bad salmon fisheries to the tune of £2,000 a year for upwards 

 of forty years. I have had also large connections with white fishermen, 

 and for thirty years had upwards of 200 men engaged for turbot, cod, 

 brill, and soles. During many years I have had great experience in 

 examining what the various fishes lived on both in the sea and river, as 

 also in the lakes. 



Most people hold that the grilse is the young of the salmon. I say it is 

 not. It is never seen on our coast till the mouth of May, and then it weighs 

 1£ to 3 pounds, while in February we have the young of the salmon 

 in our rivers weighing from li to 3 pounds. The salmon, if you examine 

 it, has an oval scale, a crescent-shaped tail, and quite a different shaped 

 body. The grilse has a diamond scale, a mackerel-shaped tail, and its 

 teeth are quite differently placed from those of the sahnou on the river 

 Forth, where I had my fisheries. I have had in one morning 300 grilse, 

 and among them upwards of 30 which exceeded 10 pounds each in 

 weight. At the same time there were GO salmon, many not over 8 

 pounds in weight, and some as high as 50 pounds. I have pointed out 

 to skeptics grilse of the second year of fully 22 pounds weight, and 

 which still retained all the above marks. 



We have a salmon hatchery on the river Tay. The keeper seemed 

 astonished to find fully one-half of his young family seemingly anxious 

 to get to sea, while the other half were quite contented to remain in 

 such good quarters. In November, when they capture the fish to take 

 the spawn from them, it is generally broken weather and often the river 

 is covered with ice or icicles, and the men getting hold of a 12 or 1G 

 pound fish never look to see whether it is an old grilse or a salmon. Thus 

 all get mixed together. This accounts for the half seeking to go to sea 

 sooner than their neighbors. Then as the salmon fry seek the sea 

 a few months earlier, it is natural for them next season to return a few 

 months earlier than the grilse. 



In some of our rivers we obtain 30 grilse for every salmon. On a 

 portion of our sea-coast for a distance of 100 miles, they do not get 100 

 salmon with the 3,000 grilse caught during the season. There is another 

 river where any quantity of fine salmon-trout are had and at times a 

 good tine grilse, but scarcely G during the season. 



Some people, and those in high positions, deny that salmon eat any- 

 thing while in the fresh water, but I have myself found hundreds of times 

 from three to eleven young herring in them during June, July, and 



