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Fishery Bulletin 96(4), 1998 
Common thresher shark 
Only 52 common thresher sharks were recorded dur- 
ing the sampling period; hence the catch rate never 
went beyond 0.1 fish/1000 hooks (Tables 5 and 6). 
The overall sex ratio was close to 1 male:2 females, 
with some differences between longline (1 male:2.16 
females) and gillnet (1 male: 1.75 females) landings. 
The size range of fish was similar for longline and 
gillnet landings, as was the mean size for both sexes 
(325 cm TL for males, 350 cm TL for females). Maxi- 
mum size was similar in longline (360 cm TL for 
males, 425 cm TL for females) and gillnet landings 
(355 cm TL for males, 435 cm TL for females). Mini- 
mum size was comparable for females in both fisher- 
ies (295 and 285 cm TL in longline and gillnet, re- 
spectively), but not for males; in longline landings, a 
245-cm-TL male was recorded, whereas in gillnet 
landings the minimum-size male recorded was about 
the same size as the minimum-size female (280 cm 
TL). Although biometrical information on this spe- 
cies is found in Table 8, our small sample size did 
not permit analyses by sex. Only one pregnant fe- 
male was recorded, measuring 385 cm TL; it was 
caught in sector 4 by longline in May and carried 4 
embryos (3 males and 1 female), 75 to 80 cm FL. 
Scalloped hammerhead shark 
The catch rate for this species was low in all sectors 
and months, slightly greater for sectors 1 and 3 (0.6 
and 0.8 fish/1000 hooks respectively), and never 
higher than 1 fish/1000 hooks (Tables 5-7). The high- 
est overall catch rates by month in longline landings 
was in November 1991 and July 1992 (1.3 and 1.1 fish/ 
1000 hooks). In gillnet landings the greatest catch rates 
were in September-October and June-July (0.1 fish/ 
unit effort). Males were more abundant in the longline 
( 1 male:0.61 females) than in the gillnet fishery, where 
females were dominant (1 male: 1.37 females). 
Females had a larger maximum size than males 
in both fisheries, 320 cm and 305 cm TL for females, 
