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FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



they are transients mostly, passing north in spring 

 and south in autumn, though some summer there; 

 even considerable numbers in some years. 33 And 

 it seems that most of them withdraw from Mas- 

 sachusetts Bay also during the warmest period, 

 for few are taken there between June and Septem- 

 ber. But they continue present all summer along 

 outer Cape Cod, and here and there throughout 

 the northern and eastern parts of the Gulf, in 

 varying abundance. 



Most of the dogfish take their autumnal depar- 

 ture from the inner parts of the Gulf during 

 October, few being caught on the coast north of 

 Massachusetts Bay after November 1. But they 

 sometimes stay later, as in 1903 (a big dogfish 

 year), and again in 1942, when they were abundant 

 along the outer shore of Cape Cod as late as the 

 first week of November. Ordinarily none are 

 caught within the Gulf of Maine north of Georges 

 Bank in winter, but this has its exceptions. In 

 1913, for example, a few were caught 20 miles off 

 Cape Ann on November 19 to 24, many near 

 Boon Island from December 5 to 13, and on 

 Jeffreys Ledge on December 11 and 12. 



In 1882, schools were reported off Portsmouth, 

 N. H., even as late as February, an exceptional 

 event. 



Dogfish appear earlier in spring and linger 

 later into the winter on Georges Bank (fig. 18) 

 than in the inner parts of the Gulf. It is safe to 

 say that there are few there in March, the earliest 

 definite record (obtained during the investigations 

 of 1913, only year of record, being of 25 fish caught 

 on the "winter cod ground" east of the shoals 

 (long, about 67°, lat. about 41°40') between the 

 20th and the 22nd, and of 46 from the same gen- 

 eral region from the 27th to the 30th, while some 

 are trawled there all summer. In 1913, a few 

 were taken in November and in December; a 

 few also on the southern part of the Bank (lat. 

 about 41°, long, about 67°30') on January 20 to 

 22 in 1914. 



Apparently dogfish reach Browns Bank later 

 than they do Georges, for none was taken there 

 on April 14 in 1913, though they are only too 

 plentiful there in summer. It is also likely that 

 they depart earlier, although a few lingered as late 

 as December 3 to 12 on Western Bank off Halifax 

 in that year. 



» For details, see Bigelow and Schroeder, Fishes of the Western North 

 Atlantic. Ft. 1, 1948, p. 464. 



Figure 18. — Numbers of spiny dogfish caught on certain 

 otter trawling trips to Georges Bank, during the dif- 

 ferent months of 1913. 



It now seems certain that the spiny dogfish 

 winter chiefly in deeper water offshore, for con- 

 siderable numbers have been trawled at that 

 season on the outer part of the continental shelf 

 off Block Island, in 50 to 65 fathoms, where we 

 saw several hundred (200 in one haul) trawled 

 during the last week of January 1950; off New 

 York in November and January; 34 also in Febru- 

 ary off the Middle Atlantic coast in 16 to 70 

 fathoms, south as far as the offing of Cape Hat- 

 teras. On the other hand, the fact that numbers 

 of them have been found washed on shore in 

 January on the southwest coast of Newfoundland 

 suggests that some of those that summer in that 

 general region may survive the winter in the deep 

 trough of the Gulf of St. Lawrence. They are 

 usually so thin when they reappear on the coast 

 in spring as to suggest that they feed but little 

 during the winter. 



This is the only Gulf of Maine shark that even 

 remotely rivals the important food fishes in num- 

 bers. Unfortunately, the statistics of the com- 

 mercial landings for American waters do not 

 afford any information in this regard. But spiny 

 dogs must be plentiful indeed in our waters when 

 they can sometimes be caught as fast as they can 



u Mr. Thomas Quast informs us that many were taken from the schooner 

 Victor, long-lining for tile fish, on the outer edge of the continental shelf, off 

 New York, during the second week of January 1928. 



