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In total, 1967 pelagic sharks of eight different species were sampled in waters of the Gulf of Guinea between June and August 1993 by commercial longline gear. Catches of Prionace glauca and Sphyma zygaena included a large number of pregnant females, making it possible to calculate some of their reproductive parameters. In total, 419 gravid females of P. glauca were caught, ranging in size from 170 to 260 cm fork length. The size at which 50% of females have embryos was determined to be 180 cm FL. Examination of the uteri from 128 of these females showed a higher number of embryos (59-60%) in the right uterus. The mean number of embryos was 37. Data on embryo size suggests that P. glauca may have a west-east migration to give birth along the Atlantic equatorial line. The embryonic sex ratio was 1 : 1. In the same catch there were 21 gravid females of S. zygaena. No difference in the number of embryos between uteri was found in this species. Mean embryo number was 33.5 and embryonic sex ratio was 1 : 1.

Abascal, F. J., Mejuto, J., Quintans, M., and Ramos-Cartelle, A. 2010. Horizontal and vertical movements of swordfish in the Southeast Pacific. – ICES Journal of Marine Science, 67: 466–474. In all, 21 swordfish (Xiphias gladius) were tagged with pop-up archival satellite tags in the Southeast Pacific. Despite problems of premature release, the information obtained provided insight into the horizontal and vertical behaviour of the species in the area. A consistent migratory pattern was observed, fish moving northwest by autumn and presumably returning south by early spring. Swordfish typically forage in deep water during the day and stay in the mixed layer at night, although this behaviour is occasionally modified. The maximum depth recorded was 1136 m, and dives deeper than 900 m were found in five of the six tags analysed. There was a significant positive relationship between average depth by night and visible moon fraction.

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The blue shark (Prionace glauca) is the most frequently captured shark in pelagic oceanic fisheries, especially pelagic longlines targeting swordfish and/or tunas. As part of cooperative scientific efforts for fisheries and biological data collection, information from fishery observers, scientific projects and surveys, and from recreational fisheries from several nations in the Atlantic and Indian Oceans was compiled. Data sets included information on location, size and sex, in a total of 478,220 blue shark records collected between 1966 and 2014. Sizes ranged from 36 to 394 cm fork length.Considerable variability was observed in the size distribution by region and season in both oceans. Larger blue sharks tend to occur in equatorial and tropical regions, and