124 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



and line fishery is carried on for salmon in the 

 Baltic, with herring for bait, while in British 

 waters salmon are sometimes caught on hooks 

 baited with launce and with pieces of mackerel. 

 Launce and capelin had been the chief diet of 

 thousands of salmon opened by Comeau 66 in the 

 northern side of the Gulf of St. Lawrence. And 

 it is probable that the salmon of the Bay of Fundy 

 and open Gulf of Maine feed chiefly on herring 

 (herring up to 5 inches long have been found in 

 salmon stomachs near Eastport) and on launce, 

 taking alewives or any other small fish as occasion 

 offers, including smelts and mummichogs (Fundu- 

 lus), when they first enter the estuaries. 67 



Salmon also feed greedily on euphausiid shrimps 

 (fish entering the Penobscot have been found full 

 of "shrimp," probably euphausiids) ; to some 

 extent on pelagic amphipods (Euthemisto) , while 

 sand fleas (gammarid crustacean) are described 

 as ranking with launce and herring as salmon 

 food in the North and Baltic Seas. Salmon are 

 also credited with eating crabs. 68 



Smolts, on the other hand, fall prey to any 

 large predaceous fish (they have been found in 

 the stomachs of pollock), but salmon are so heavy 

 and strong after one or two years' sojourn in salt 

 water that only fish as large as tuna, swordfish, 

 or the larger sharks can menace them. Their 

 worst enemy is the harbor seal, which is a com- 

 mon inhabitant of the northeastern coasts of the 

 Gulf of Maine and of the Bay of Fundy. 



The young smolts grow so rapidly on the abun- 

 dant diet the sea affords that they usually reach 

 a length of at least 16 inches and a weight of any- 

 where from % to 7 pounds after one year at sea. 

 They are now known as "grilse." And older sal- 

 mon continue to put on length and weight very 

 fast, as long as they remain in salt water. Thus, 

 several St. John fish which were tagged and re- 

 leased in the river in the autumn after spawning 

 and which were recaptured the following summer 

 after wintering in the sea had gained 2 to 8 pounds 

 in weight, one of them more than 6 inches in length. 

 Others which spent two uninterrupted years in 

 the sea (as shown by their scales) averaged about 



* Life and Sport on the North Shore, 1909, Quebec. 



i Kendall (Mem. Boston Soc. Nat. Hist., vol. 9, No. 1, 1935, p. 34) found 

 smelts in Penobscot salmon, alewives in salmon from the St. John. 



» See Kendall (Mem. Boston Soc. Nat. Hist., vol. 9, No. 1, 1935, pp. 33-34) 

 for a recent survey of the diet of salmon in general; the Oulf of Maine fish in 

 particular, with references. Etchelbaum (Cons. Perm. Internal. Explor. 

 Mer, Rapports et Proc. Verb., vol. 21, 1916, p. 84) records the contents of 

 many salmon from the Baltic and from the North Sea. 



10 pounds heavier and 6 inches longer when re- 

 captured. 69 But they grow much less rapidly in 

 winter than in summer. And they hardly grow 

 at all during the years when they spawn if they 

 enter the river early in season, though they con- 

 tinue growing until later if they enter late. Hence 

 the size of a salmon depends more on the number 

 of times it has spawned and on the date when it 

 enters its river than on its age. 



Most of the exceptionally large fish of 40 to 50 

 pounds are virgin females entering fresh water for 

 the first time, but some are fish that have already 

 spawned once. An interesting case is that of a 

 45-pound 2-ounce fish, caught in the Moisie River, 

 on the north shore of the Gulf of St. Lawrence, 

 June 1950, by E. E. Steedman, the life history of 

 which had been as follows: 60 hatched spring 1942; 

 went to sea June 1945; returned to river and 

 spawned there in 1948; returned to sea autumn 

 1948; remained there until June 1950; then re- 

 turned to the river, to be caught on a "Lady Am- 

 herst" fly; age 8 years. 



Some salmon become "river mature" and return 

 to spawn after only one year at sea; these, known 

 as grilse, are distinguishable from the older fish 

 by more forked tail, more slender body, thinner 

 scales, and more numerous spots that are blue 

 rather than black. 61 Some spawn 2 or 3 years in 

 succession, and hence never grow large; others 

 spawn twice in alternate years; a few three times, 

 very few oftener. It follows from this that large 

 salmon are to be found in the sea throughout the 

 year, though fewer of them in summer when the 

 spawning fish are in the rivers, than in winter 

 when the whole stock is in salt water except for 

 the "parr," a few immature grilse (p. 129), and 

 such of the spent fish as winter in the rivers. 

 Some spawn only once after 3, 4, or even 5 years 

 at sea, growing to a great size meantime. But 

 very few salmon five to be more than 8 or 9 

 years old, including the time spent in fresh water 

 as parr. 



Our ignorance of the way of life of the salmon 

 in the sea has recently been characterized as 

 abyssmal. Certainly they are swift swimmers, 

 and the nature of the catches suggests that they 



» Huntsman (Bull. Biol. Board Canada, No. 21, 1931) gives an interesting 

 account of these tagging experiments, from which this summary is drawn. 



» As worked out from its scales by Dr. D. L. Belding, and reported in 

 Field and Stream, August 1951, p. 10. 



•' It is commonly stated that this applies chiefly to the males. But Hunts- 

 man (Bull. Biol. Board Canada, No. 21, 1931, pp. 18-19) has found that grilse 

 of both sexes spawn in the small rivers at the head of the Bay of Fundy. 



