FISHES OF THE GULF OF MAINE 



43 



and upper part of the sides, including the pectorals, 

 but this shark has also been described as pale 

 gray above or even dirty white, perhaps over a 

 white sand bottom. The trunk is white below, 

 the pectorals grayish, darkening to sooty at their 

 tips; the pelvics and anal fins grayish white. 



Size. — -The usual length at birth is a little more 

 than three feet.* Adult dusky sharks so far 

 measured have ranged from 10 feet 4 inches to 

 11 feet 8 inches in length, and they are said to 

 grow to 14 feet, though perhaps not on very 

 convincing evidence. 



General range. — Western Atlantic, north to 

 southern New England and to Georges Bank, 

 south to southern Brazil, at least by name. A 

 shark very closely allied to obscurus has been 

 reported under that name in the eastern Atlantic, 

 from Spain to Table Bay, South Africa, including 

 Madeira, the Canaries, the Cape Verdes, Ascen- 

 sion Island, and St. Helena. But we have yet 

 to learn its precise relationship to the obscurus of 

 the western Atlantic. 



Occurrence in the Gulf of Maine. — The dusky 

 shark has been taken repeatedly off the coasts of 

 New Jersey and of Long Island, N. Y.; also at 

 Woods Hole, where we have handled 12 specimens 

 during the past few summers, 6 of them in August 

 1944. But it so seldom strays to cooler waters 

 farther east that only one shark has been recorded 

 from Nantucket, and one from Georges Bank, 

 that probably were of this species and not some 

 other carcharhinid. 6 Thus it has no real place in 

 the fauna of the Gulf. 6 



Brown shark Carcharhinus milberti (Miiller and 

 Henle) 1841 



Sand bar shark 



Bigelow and Schroeder, 1948, p. 368. 

 Garman, 1913, pi. 3, figs. 4-6 (as Carcharinus platyo- 

 don). 



Description. — The brown shark differs from the 

 dusky (only member of its genus that seems 

 actually to have been taken within the Gulf) in 



the more forward position and larger size of its 

 first dorsal fin, in its broader pectorals, and in its 

 stouter trunk, heaviest forward (compare speci- 

 mens in figure 14). Also, the anterior edge of its 

 nostril is expanded as a low but definite triangular 

 lobe, which is not the case in the dusky shark. 

 Other characters (in combination) that mark it 

 off from other members of this genus that might 

 stray to the Gulf are: Mid-line of the back with 

 a low ridge between the two dorsal fins; snout 

 forward of a line connecting the front margins of 

 the nostrils, considerably shorter than the distance 

 between the nostrils; point of origin of second 

 dorsal fin about over origin of anal fin, its free 

 rear corner only a little longer than the height 

 of the fin; apex of first dorsal fin angular; length 

 of pectorals along anterior margin about as great 

 as distance from tip of snout to level of second 

 pair of gfil openings; distance from rear tips of 

 pelvic fins to origin of anal fin as long as base of 

 anal fin, or longer, fifth gill openings longer than 

 horizontal diameter of eye. 



The teeth resemble closely those of the dusky 

 shark (see figure 14). 



Color. — Upper surface slate gray to brown; 

 lower surface a paler tint of the same hue, or 

 white; fins without any conspicuous black mark- 

 ings. When alive some of the dermal denticles 

 are bright blue, at least on some specimens. 



Size. — Sexual maturity is reached at a length 

 of about 6 feet; maximum length about eight feet. 7 



General range. — Southern Brazil, Louisiana, both 

 coasts of Florida, and northward along the Atlantic 

 coast of the United States to southern New 

 England; also the tropical-subtropical belt of the 

 eastern Atlantic, and the Mediterranean, or 

 represented there by an extremely close relative. 8 



Occurrence in the Gulf oj Maine. — Next to the 

 sand shark, this is the most numerous of the 

 larger sharks along the coasts of New Jersey and 

 of New York. Some visit the vicinity of Woods 

 Hole, though so few that the number taken there 

 in most summers probably is not greater than six 

 or seven. It has not been reported as yet from 



* Embryos have been reported up to 38 In. long (965 mm.), and a free living 

 specimen of only 39 In. (993 mm.) ; see Bigelow and Schroeder, Fishes Western 

 North Atlantic, Pt. 1, 1948, p. 387. 



» Probably this species and not the brown shark because 11-12 feet long. 



I In the first edition of this book, the dusky shark was said to have been 

 taken at three localities within the Gulf. But one of these records, at least, 

 was almost certainly based on a blue shark, and the others probably were 

 (Bigelow and Schroeder, Fishes Western North Atlantic, Pt. 1, 1948, pp. 

 292, 368). 



' Seven feet 10 Inches is the greatest measured length that we have found 

 recorded, with convincing evidence that the specimen actually was one of 

 this species. 



•If the eastern Atlantic-Mediterranean form Is actually Identical with 

 the American, as seems to be the case, the specific name milberti of Miiller 

 and Henle, 1841, must be replaced by plumbeus proposed by Nardo In 1827 

 for the brown shark of the Adriatic. 



