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FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



(as was previously suspected) that most of the 

 wanderings of the Gulf of Maine haddock are of 

 short extent. Thus 34 fish that had been tagged 

 on Nantucket Shoals were recaptured nearby, 

 16 after periods longer than 200 days; only 

 10 were captured at a distance. And the pre- 

 ponderance of relatively stationary fish is even 

 more impressive for the vicinity of Mount Des- 

 ert Island, where 1 14 tagged fish were recaptured 

 within a few miles of the tagging stations after 

 an average period of 224 days, contrasting with 

 recaptures of only 25 of them at a distance. 



The haddock of the coasts of Massachusetts 

 and of western Maine, with the offlying banks, 

 may be less stationary, for only two of the fish 

 that were tagged on Stellwagen Bank and be- 

 tween Boone Island and Boothbay were recap- 

 tured locally; 13 of them far afield. 



The tagging experiments do not suggest that 

 such of the Gulf of Maine haddock as do wander 

 follow any regular migratory routes. Thus some 

 of the few Nantucket Shoals fish that are known to 

 have strayed were recaptured to the eastward 

 (eastern part of Georges Bank, 2) ; some of them 

 to the northward (western side of Gulf and Platts 

 Bank, 6); and some to the northeastward (nor- 

 thern entrance to Bay of Fundy, 2). Conversely, 

 it was in the opposite direction, i. e., to Platts 

 Bank, to the coasts of western Maine and of Mas- 

 sachusetts, to the South Channel, and to Georges 

 Bank that wanderers are known to have strayed 

 from the Mount Desert tagging ground. And 

 the few fish that were recaught from those tagged 

 at localities intermediate between Nantucket 

 Shoals and Mount Desert, have fanned out in 

 various directions. 



An obvious reason why haddock of the New 

 England population, that commence their adult 

 journeyings in the northeastern part of the Gulf, 

 should tend to stray southwestward, southward, 

 and perhaps then eastward along Georges Bank, 

 whereas others, commencing in the southwest 

 should tend either eastward, or northward and 

 then northeastward, is that these are the only 

 routes left wide open to them within the Gulf, 

 between the coastline on the one side and the 

 barrier that is set for them by the 100-fathom 

 depth line on the other side. How effective is 

 this barrier is emphasized by the fact that only 

 one fish, among 9,416 that we tagged off the coasts 

 of Massachusetts and of Maine was recaptured 



in Nova Scotian waters (it had gone from Mount 

 Desert to the southern side of the Bay of Fundy) ; 

 and that none of the haddock that were tagged in 

 Nova Scotian waters by the Biological Board were 

 recaptured west of the Fundian Channel. 



Very little is known as to the shifts in location 

 and in depth that haddock may make between 

 winter and summer, the difficulty lying in the in- 

 terpretation of the differences from season to 

 season in the amounts of haddock that are caught 

 on neighboring grounds in the inner parts of the 

 Gulf." 



In general, it appears that when the temperature 

 of the upper 15-20 fathoms of water rises above 

 about 50° to 52° F., as happens along the coasts 

 of Maine and Massachusetts in July or August, 

 the haddock tend to withdraw from the shallower 

 grounds where they are plentiful in spring and 

 early summer. But certain bodies of fish may 

 linger all summer in the deeper channels among 

 the islands of Maine, on patches of suitable bot- 

 tom. In 1923, for instance, haddock were caught 

 throughout July, August, and September, be- 

 tween Suttons Island and Bear Island, near 

 Mount Desert Island, as well as at other inshore 

 localities near by. Fishermen report them as 

 working inshore again in autumn or early winter, 

 as the water cools, but those that come closest 

 inshore then are supposed to work out again, in 

 mid and late winter, to avoid extreme chilling. 

 Thus few or none are caught at that season in the 

 Bay of Fundy, where the temperature may fall as 

 low as 32° in occasional winters, 80 though it does 

 not drop below 34° to 36° in most years. 



We must caution the reader, however, that 

 these supposed disappearances in winter from 

 inshore localities are based on failure to catch 

 haddock then on hook and line, which may actu- 

 ally result more from a reluctance on their part to 

 bite at low temperatures (p. 202) than from sea- 

 sonal scarcity of fish. Experimental trawlings at 

 different seasons are needed to clarify this matter. 

 At any rate, the temperatures of the open Gulf 

 of Maine at the depths where haddock are the 

 most plentiful never fall too low for their comfort 

 in the winter, nor rise too high in the summer. 



™ Rich (Rept. U. S. Fish Coram, for 1929, 1930, App. 3) gives information 

 In this respect. 



" As happened In 1928 (Needier, Contrlb. Canadian Biol, and Fish., N. 

 Ser., vol. 6, No. 10, 1930, p. 19 [259]). 



