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Fishery Bulletin 93(2). 1995 



Atlantic specimens may not attain that size. Our 

 longest tiger shark was 339 cm FL ( 11.1 ft) (Table 2). 

 The maximum reported length examined by Bran- 

 stetter (1981) in a study of tiger sharks in the north 

 central Gulf of Mexico was 346 cm FL (11.4 ft). The 

 maximum reported length for the U.S. Atlantic coast 

 is 391 cm FL (12.8 ft) (Bigelow and Schroeder, 1948). 

 These lengths are more in agreement with individu- 

 als sampled in this study. 



Specimens from three species of sharks exceeded 

 the maximum reported lengths (Table 2): sandbar 

 shark, shortfin mako shark, and scalloped hammer- 

 head shark. The 211 cm FL (6.9 ft) female sandbar 

 shark in this study (Table 1) was measured by one of 

 the authors (J. Casey) and is the largest measured 

 sandbar reported to date. This fish was caught in 

 September of 1964 by a sport fisherman approxi- 

 mately 10 miles east of Asbury Park, New Jersey. 

 Unfortunately, the fish was not weighed. Two mako 

 sharks measured in this study were longer than the 

 336 cm FL (11.0 ft) maximum size fish published in 

 the literature. Both of these fish were 338 cm FL 

 (11.1 ft) females caught by sport fishermen south of 

 Montauk Point, New York. One was landed in July 

 of 1977 and weighed 471 kg (1,039 lbs). The other 

 was caught in August of 1979 and weighed 382 kg 

 (841 lbs). The largest scalloped hammerhead (243 

 cm FL, 8.0 ft; 166 kg, 365 lbs) was measured at a 

 sportfishing tournament in July of 1985 and was 

 caught 36 miles southeast of Highlands, New Jersey. 



The lower ends of the length-weight curves also 

 compare well with published estimates of size at birth 

 for each species of shark. Pratt and Casey ( 1990) give 

 maximum size at birth in TL for 11 of the 13 species 

 of sharks sampled here and all except the thresher 

 shark are within 40 cm (16 in) of those sizes. Our 

 smallest thresher shark is 64 cm (25 in) larger than 

 the reported birth size. 



All of the larger fish were female with the excep- 

 tion of the white and the blue shark (Tables 1 and 2). 

 The larger size attained by females is typical of 

 sharks in general (Pratt and Casey, 1983; Hoenig and 

 Gruber, 1990), and thus larger female blue and white 

 sharks very likely occur outside of our western North 

 Atlantic sampling area which only covers a small 

 portion of their extensive oceanic range. 



Blue sharks have a complex life history cycle and 

 large females are infrequent visitors to the continen- 

 tal shelf and slope waters off North America. The 

 shelf area serves as a mating ground where the catch 

 consists primarily of juvenile males and females, 

 subadult females, and adult males (Casey, 1985). The 

 occurrence of considerable numbers of the larger fe- 

 males (>240 cm, 7.9 ft) is rare in the western North 

 Atlantic, but numerous large gravid females have 



been reported in the eastern Atlantic from the Medi- 

 terranean Sea and around the Madeira and Canary 

 Islands (Aasen, 1966; Pratt, 1979). 



The white shark distribution pattern may be as 

 complex as that of the blue shark but is more ob- 

 scure. Although no mature female white sharks were 

 examined, adult females have been reported from the 

 western North Atlantic. Casey and Pratt (1985) de- 

 scribe a 483 cm FL (15.8 ft) fish harpooned off 

 Montauk, New York, in 1964 and a 526 cm FL ( 17.3 

 ft) female which became entangled in a gill net near 

 Prince Edward Island, Canada, in July, 1983. Else- 

 where, large female white sharks have been reported 

 in the Gulf of Maine (Bigelow and Schroeder, 1948; 

 Skud, 1962), in the Mediterranean Sea (Ellis and 

 McCosker, 1991) and off the west coast of Florida 

 (Springer, 1939). Catching a large white shark of ei- 

 ther sex, however, is an uncommon event. White 

 sharks are likely to occur singly or as scattered, 

 unassociated individuals over vast geographical ar- 

 eas ( Casey and Pratt, 1985 ). Owing to their immense 

 size, they are difficult to catch and are capable of 

 breaking free of most conventional fishing gear. 



Factors affecting weight 



Weights of individual sharks of the same length may 

 differ depending on several factors, including the 

 amount of stomach contents, the stage of maturity, 

 the liver weight, and the condition of the shark. The 

 effects of stomach contents on the weight of the fish 

 were minimal in this study. In many instances, the 

 sharks everted their stomachs prior to being weighed. 

 For the bigger fish, when large amounts of food were 

 present, the weight of the stomach contents was sub- 

 tracted to obtain the total body weight. Since not 

 every shark was examined internally, some pregnant 

 fish may have been inadvertently included in the 

 database. 



Differences in body weight also reflect differences 

 in the condition of an individual. Sharks have large 

 livers which store high energy, fatty acids for buoy- 

 ancy and for use as a food reserve (Bone and Rob- 

 erts, 1969; Oguri, 1990). The weight of this organ is 

 thus a good indicator of the health or condition of a 

 shark (Springer, 1960; Cliff et al., 1989). The liver is 

 the largest organ by weight in the shark and can 

 vary from 2-24% of the body weight depending on 

 the species (Cliff et al., 1989; Winner, 1990). Varia- 

 tion in the liver size accounted for the majority of 

 the weight difference in individuals of the same spe- 

 cies with corresponding lengths. In six of the eight 

 largest white sharks, the liver weights ranged from 

 14.6-22.7% of the body weight (hepatosomatic index, 

 HSI) (Table 3). The 458 cm (15.0 ft) FL white shark 



