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FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



winter in the mid-depths, not concentrated on 

 the bottom. This, however, would imply that 

 the wintering mackerel manage to hold position 

 for two or three months in some way without 

 drifting far with the movements of the water. 

 Another possibility is that they do keep on bottom, 

 or near it, but somewhat deeper down the contin- 

 ental slope than the trawlers ordinarily fish, 40 

 perhaps concentrated in the many gullies, large 

 and small, with which the upper part of the slope 

 is seamed all along from the offing of Chesapeake 

 Bay to Georges Bank, much as the mackerel of 

 the Celtic Sea and English Channel winter "on 

 the sea floor, densely packed in places where its 

 level is interrupted by banks and gullies." 41 



Whichever of these alternatives is the correct 

 one, the oft repeated assertion that the adipose 

 eyelids of the mackerel become opaque in winter 

 has no foundation. And they certainly do not 

 hibernate in thousands along the coasts of Green- 

 land and Hudson Bay, 42 and of Newfoundland, 

 with heads in the mud and tails protruding as a 

 vice admiral, no less, has described them; a 

 wholly imaginary tale, we need hardly add. 43 

 They may winter in a more or less sluggish state. 

 But the presence of food in the stomachs of some 

 of the winter-caught fish, added to the fact that 

 some of them are fat though others are thin, 

 shows that they move about more or less even 

 then, and feed more or less. 44 



Most American students have looked on the 

 vernal warming of the surface water to about 

 45° F. as the stimulus causing the mackerel to 

 quit their winter quarters. European studies, 

 however, have shown that the date of their re- 

 appearance in spring is not closely associated with 

 any particular temperature. And if the mackerel 

 winter on bottom along the edge of the continent, 

 vernal changes in the temperature of the surface 

 water nearer to land would be wholly outside 

 their ken. 



The European mackerel usually keep to the 

 bottom on their spring migration until close in to 

 the land before rising to the surface. But this 



<° The southern trawl fishery is mostly shoaler than 70 fathoms. 



« Steven, Jour. Marine Biol. Assoc. United Kingdom, vol. 27, 1948, p. 537. 



« Mackerel do not range that far north. 



« Cited from Lacepede, Hist. Nat. Poissons, vol. 3, in Buffon, Hist. Nat- 

 urelle, 1802, p. 32. 



** Ehrenbaum (Rapp. et Proces Verbaux, Cons. Perm. Internat. Explor. 

 Mer, vol. 18, 1914, p. 13), whose studies of the fish entitle his view to great 

 weight, thinks that the mackerel of northern Europe probably are torpid 

 during part of their stay on the bottom. 



generalization does not apply to the American fish, 

 for while some may 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 great num- 

 bers are first sighted 30 to 50 miles offshore, and 

 this all the way from the latitude of Cape Hatteras 

 to the mouth of the Gulf of Maine. The first 

 mackerel "show" off the Cape Hatteras region at 

 any time between about March 20 and April 25, 

 usually early in April, and by the middle of 

 April off Delaware Bay. As the water warms 

 they spread northward and shoreward, being 

 joined, it seems, by additional contingents from 

 offshore. They reach the offing of southern New 

 England some time in May, and they are plentiful 

 on Nantucket Shoals by the first week of that 

 month, as a rule. 



The date when they are first sighted off Cape 

 Cod in the southwestern part of the Gulf of 

 Maine varies from the last of April or first of 

 May (April 29 in 1901, May 2, in 1898) to the 

 first of June, with May 10 about the average. 

 The earliest dates of commercial catches, for 

 example, made in one particular set of traps near 

 Provincetown have varied between May 14 and 

 June 19. And the fish are plentiful in the western 

 side of the Gulf of Maine as a whole by the end 

 of the first week in June at the latest, if it is fated 

 to be a good mackerel year. Mackerel (usually 

 in smaller numbers) also appear on the Nova 

 Scotian side of the Gulf about as early as they do 

 in its western side; thus they were reported almost 

 simultaneously off Yarmouth, Nova Scotia, and 

 off Chatham on Cape Cod in 1898; in 1922 they 

 were sighted off Yarmouth on May 7th, and off 

 Cape Sable on the 11th. And they may appear 

 even earlier in the season at Cape Breton, and as 

 early well within the Gulf of St. Lawrence and 

 in the eastern side of our Gulf. In 1894, for 

 example, mackerel were first reported off Cape 

 Breton on May 5 and at Gaspe on May 12, but 

 not until May 16 45 at Yarmouth on the Gulf of 

 Maine coast of Nova Scotia. But few of them 

 show along the coast of Maine or in the Bay of 

 Fundy until toward the end of June. 



Sette 4e has made the very interesting discovery 

 that two distinct populations are represented 

 among the American mackerel, a southern and a 



<» Huntsman, Canadian Fisherman, vol. 9, no. 5, 1922, pp. 88-89. 

 « Fish. Bull. U. S. Fish and Wildlife Service, vol. 51, Bull. 49, 1950. 



