FISHES OF THE GULF OF MAINE 193 



first comers being recruited later by part of the schools that are seen on Nantucke 

 Shoals and Georges Bank in May, but it seems certain that considerable bodies of 

 mackerel remain on these offshore grounds all summer, both spawning and feeding 

 there, these, with the recruits they may receive from the south during the years of 

 plenty, providing good fishing there any time from June to September. 



An interesting question is whether a given school returns summer after summer 

 to the same general part of the coast (that is, to the Gulf of Maine),. or whether 

 there is considerable interchange and a wide shifting of grounds. Within moderate 

 limits the last alternative is probably the correct one, but experience on the other 

 side of the Atlantic, where it has been possible to recognize local races of mackerel, 33 

 makes it seem very unlikely that fish resorting to the Gulf of Maine or its offshore 

 banks one summer would visit a region as far afield as the Gulf of St. Lawrence 

 another. 



On their spring migration the European mackerel usually keep to the bottom 

 until close in to land before rising to the surface. This generalization does not apply 

 to the American fish, however, for while some swim deep — so, only, can we account 

 for the fact that the first schools often show as early in Massachusetts Bay as on 

 Georges Bank or off Nantucket — mackerel in much greater numbers come to the 

 surface as far out as the edge of the continental shelf in spring, and this all the way 

 from the latitude of Cape Hatteras to the mouth of the Gulf of Maine. 



Date of appearance. — The first mackerel are expected off the Chesapeake Bay- 

 Cape Hatteras region at any time between March 20 and April 25; off the Dela- 

 ware Capes during the last half of April; off southern New England in May. May 

 10 may be set as about the average date of their appearance in the southern part 

 of the Gulf of Maine, and they are usually plentiful on Nantucket Shoals by that 

 time. The date of their appearance may vary a week or more in either direction 

 in different years. In 1898, for instance, mackerel were reported simultaneously at 

 Chatham on Cape Cod and at Yarmouth, Nova Scotia, on May 2; in 1901 they 

 were seen off Chatham on April 29; and in 1922 the first schools were sighted south 

 of Cape Sable on May 11 and off Yarmouth on the 7th; but if it is fated to be a good 

 mackerel year the fish are plentiful in most parts of the Gulf of Maine by the end 

 of May or the first week in June at the latest, except in the Bay of Fundy where 

 few appear until well into the latter month. 



Movements in summer in the Gulf of Maine. — Though we can not offer definite 

 evidence to this effect, it is safe to say that after they once appear on the coast 

 the wanderings of the immature mackerel are wholly governed by their search for 

 food. This is equally true in the case of the large fish after spawning is completed, 

 that is, during the last half of the summer, but when the latter first arrive the case 

 is complicated by their sexual activity (p. 206) . General report has it, on the basis 

 of the gill-net and pound-net catches (and there is no reason to doubt this), that 

 the adult mackerel that spawn in Massachusetts Bay come in around Cape Cod, 

 but that other bodies swim directly in to the coast of Maine, and that the fish 

 bound for the Bay of Fundy and for the northeast corner of the Gulf generally, 



» The American mackerel does not split up into local races. 



