NOTES ON THE REPRODUCTION OF THE OCEANIC WHITETIP SHARK, CARCHARHINUS LONGIMANUS, IN THE SOUTHWESTERN EQUATORIAL ATLANTIC OCEAN

A total of 104 oceanic whitetip sharks, 57 males and 47 females, were caught in the southwestern equatorial region and examined for their reproductive biology. Total length (TL) ranged from 72 to 253cm in males and from 74 to 252cm in females. These preliminary data suggest that size at first maturity is occurring from 160 to 196cm in males and from 181 to 203cm in females. A high proportion of the catch was composed by immature specimens, specifically 80.7% of males and 89.4% of females, suggesting a spatial size-segregation of this population. Three pregnant females were caught, with litters varying from 1 to 14 embryos. Even though at this stage there are not enough data to propose a reproductive cycle for this population, we forward the hypothesis that mating may be occurring early in the year, around March, and parturition might be occurring 10 to 12 months later, around January. As more data become available in this on-going study, we expect to define more clearly the size at maturity and the reproductive cycle of the oceanic whitetip shark for the southwestern equatorial region of the Atlantic Ocean. RÉSUMÉ