PARAMETRI RIPRODUTTIVI DEL TURSIOPE (TURSIOPS TRUNCATUS) NEL SANTUARIO PELAGOS (MAR MEDITERRANEO NORD-OCCIDENTALE)

REPRODUCTIVE PARAMETERS OF BOTTLENOSE DOLPHIN (TURSIOPS TRUNCATUS) IN THE PELAGOS SANCTUARY (NORTH-WESTERN MEDITERRANEAN SEA)

Abstract

Understanding reproductive parameters in female bottlenose dolphins (Tursiops truncatus) is essential for evaluating population health and guiding conservation strategies. From 2001 to 2024, 587 sightings of bottlenose dolphins were recorded within the Pelagos Sanctuary (north-western Mediterranean Sea), and 530 individuals were photo-identified, including 113 females. This study assessed variations in female behavior according to the presence of calves, considering group size, spatial distribution, home range and social structure. A further objective was to investigate the reproductive behaviour of the common bottlenose dolphins in the study area, the fertility rate of females and the mortality rate of newborns. Results indicate that female behavior differs depending on calf presence. Estimated reproductive parameters were: total fertility rate 0.19, calving interval 4.49±0.19 (SE) years and calf mortality within the first year 0.23. These values are consistent with previous studies and update earlier findings, providing new insights into the reproductive dynamics of this population.