Labrador (Bigelow and Schroeder, 1948). It is 

 common northward along the coasts of Newfound- 

 land. There is no record of its occurring along 

 the coast north of Hamilton Inlet. Offshore it 

 occurs in season on Nantucket Shoals, Georges 

 Bank, Browns Bank, the Nova Scotian banks, and 

 the Newfoundland banks. It was also recorded on 

 the west coast of Greenland to Sukkertoppen and 

 Holsteinborg. Hansen (1949) reports that dog- 

 fish were formerly a rarity around Greenland, but 

 in the 1930's some were caught in several places on 

 the southwest coast and in the autumn of 1947, 

 around Sukkertoppen. 



Local observations of spiny dogfish, and their 

 seasonal occurrence, are reported by Perley 

 (1852), Stafford (1912), Cox (1921), and Jeffers 

 ( 1932) . Each of these authors noted that the ap- 

 pearance of dogfish usually indicated an end of 

 commercial fishing for food fishes. 



Table 1. — Water temperature and dogfish catches of 100 or 

 more by otter trawl from research vessels in the Northwest 

 Atlantic from Nova Scotia to the offing of New York, 

 1948-59 



Date 



Feb. 3, 1959... 

 Do 



Apr. 22, i950.. 



Apr. 23, 1950. . 



Apr. 26, 1950.. 

 Do 



May 1, 1950... 



Do 



Do.. 



Do 



May 2, 1950... 



May 13, 1950.. 



Do 



Do 



Do 



May 14, 1950. 



May 15, 1950. 



May 16, 1950. 

 Do 



May 17..1950. 



June 14, 1955-. 



Weighted average- 



July 29, 1949 - 

 Aug. 1, 1950... 



Do 



Aug. 2, 1950... 

 Aug. 5, 1950... 

 Aug. 4, 1948— 

 Aug. 5, 1948... 



Do 



Oct. 8, 1958.-- 

 Oct. 9, 1958 ... 

 Oct. 16, 1948 . 

 Oct. 17, 1948 . 

 Oct. 20, 1959. . 

 Oct. 30, 1949.. 



Do 



Do 



Do 



Oct. 31, 1948 . 

 Nov. 5, 1948. . 

 Nov. 17, 1956. 



Do 

 Dec. 3, 1948... 



Weighted average- 



Depth 



Meiers 



180 



152 



122 



110 



219 



219 



189 



183 



177 



201 



110 



91 



91 



82 



81 



83 



142 



113 



85 



76 



103 



67 

 85 

 85 

 94 

 293 

 58 

 33 

 40 

 204 

 222 

 24 

 37 

 55 

 74 

 76 

 60 

 55 

 61 

 61 

 56 

 56 

 85 



Bottom 

 tempera- 

 ture 



9.4 

 11.7 

 9.4 

 7.2 

 7.8 

 7.2 

 8.9 



8.9 

 4.4 

 11.1 

 11.1 

 11.1 

 5.0 

 7.2 

 11.1 

 7.8 

 6.7 

 5.6 

 6.1 



8.3 



10.6 

 7.8 

 8.3 

 8.9 

 6.1 

 6.7 

 13.3 

 11.7 

 7.8 

 7.8 

 12.2 

 8.3 

 11.1 

 15.6 

 13.3 

 14.4 

 15.6 

 15.0 

 14.4 

 13.3 

 16.7 



85 



Catch of 

 dogfish 



Number 

 428 

 367 

 560 

 100 

 103 

 224 

 372 



1,200 

 475 

 269 

 420 



1,476 

 152 

 150 

 610 

 258 

 110 

 120 

 140 

 156 

 110 



3,637 

 224 

 455 

 146 

 234 

 123 

 131 

 210 

 900 

 122 

 374 

 101 



1,050 

 248 

 100 

 283 

 115 



1,561 

 187 

 160 

 211 

 190 



In the Pacific Ocean, Bigelow and Schroeder 

 (1948) report that the spiny dogfish is found on 

 ". . . both sides of the Northern Pacific south to 

 California, Japan, Northern China and the 

 Hawaiian Islands." 



MIGRATIONS 



The spiny dogfish is a gregarious fish and occurs 

 in schools containing large numbers of individ- 

 uals. Usually the schools are composed of: (1) 

 very large, mature females; (2) medium-sized in- 

 dividuals, all mature males or all immature fe- 

 males; or (3) small immature individuals of both 

 sexes in about equal numbers (Bigelow and 

 Schroeder, 1953 ) . Hickling ( 1930) , in his studies 

 of spiny dogfish collected off the southern coast of 

 Ireland, noted a relation between the size of the 

 individuals in the schools and the depth of water. 

 Fish of both sexes, from 30 to 45 cm. long, were 

 caught in 55 m., while larger fish of both sexes, 

 from 50 to 89 cm. long, were caught in depths of 

 164 to 183 m. In general, male dogfish were found 

 in shallower water than females of the same size. 

 The exception to this, however, was for the large 

 pregnant females that were found migrating into 

 shallower water to bear their young. 



The. appearance of dogfish in our northeastern 

 coastal waters is a rather sudden event. One day, 

 in a given area, there will be fine cod and haddock 

 fishing; the next day there will be nothing but 

 dogfish. They appear as early on Georges Bank 

 (March- April) as they do along New Jersey 

 (March) (Bigelow and Schroeder, 1953). Dog- 

 fish are spring and autumn transients only in the 

 southern part of their range, from New York to 

 North Carolina, and in the Cape Cod area they 

 are mostly transients, moving to the north in the 

 spring and to the south in the autumn. 



In Newfoundland waters they first begin to ap- 

 pear in June, off the southern end of the island 

 (Templeman, 1944). The largest fish— mature 

 and probably pregnant females — appear first. 

 The mature males appear in the late autumn. As 

 the season progresses, dogfish appear farther 

 northward along the coast and are off Labrador 

 by September. In general, dogfish are plentiful 

 around Newfoundland from June through No- 

 vember or December. 



The nature of the dogfish's seasonal migration — 

 coastal north-south, offshore-onshore, or a combi- 



530 



U.S. FISH AND WILDLIFE SERVICE 



