FISHES OF THE GULF OF MAINE 241 



of its destructive habits, the bluefish "not content with what they eat, which is 

 itself of enormous quantity, rush ravenously through the closely crowded schools, 

 cutting and tearing the living fish as they go." Not only the schooling fish, but 

 scup, squeteague, hake, butterfish, cunners, and in fact small fish of all kinds,' as 

 well as squid, fall prey to them. Baird estimated that in the early seventies, when 

 bluefish were at the height of their abundance, they annually destroyed at least 

 twelve hundred million fish during the four summer months off southern New 

 England alone ; and while from the nature of the case no such calculation can claim 

 even an approach to accuracy, it will at least help give the reader a graphic realiza- 

 tion of the destruction they wreak diu-ing their periods of plenty. They are also 

 known to eat various Crustacea and even marine worms on occasion, and the 

 young "snappers" 6 to 8 inches long feed largely on copepods, crustacean and 

 molluscan larvse, as well as on fish fry smaller than themselves. 



Bluefish are creatures of warm water. In the years when they pass Cape Cod 

 they usually appear in Massachusetts Bay about the middle and sometimes as 

 early as the 1st of June,' and are seen off and on all summer. Most of them 

 depart late in September, but an occasional fish lingers into late autumn. Bluefish 

 have even been caught about Provincetown as late as December. It is not known 

 where these northern bluefish winter, nor even whether they migrate southward 

 along shore or move out to sea. 



No fully ripe bluefish have ever been taken so far as we can learn, although 

 females containing large ova approaching ripeness are often seen in summer on 

 various parts of the American coast. While their spawning grounds are still to 

 be discovered, it is not likely that they spawn in inshore waters along the New 

 England coast, and though they may do so along the shores of the Middle and South 

 Atlantic States, we incline to the view now generally held that the chief production 

 of eggs takes place out at sea before the fish appear on the coast. The possibdity 

 is still open, however, that the buoyant eggs with segmented yolk and large oil 

 globule from Newport, R. I., provisionally referred to the bluefish by Agassiz and 

 Whitman (1885), were actually those of this species, and while the identity of 

 their "bluefish" larvae has likewise been questioned, we believe that their identi- 

 fication of the oldest (9 mm.) was correct, though the younger ones may have 

 belonged to some Scombroid. 



At this stage the second dorsal fin is formed, the first, however, still repre- 

 sented by the rudiments of the future spines. The anal fins are visible, also, and 

 the tail is slightly forked. These larvae, like mackerel (which they much resemble) , 

 have large blue eyes and large projecting teeth, but they are as far advanced in 

 development as mackerel twice as large, and in proportion to their size they are as 

 ferocious as the adult bluefish are, devouring all other small animals kept in the 

 tank with them. 



The bluefish fry of three-fourths to 3 inches, which have often been taken 

 along shore in summer not only south of Cape Cod but even in the GuK of Maine 

 (p. 240), are presumably the product of that spring's spawning, and it seems that 



' Along southern New England thoy are expected during the last half of May. 



