Assessment of multiple paternity in spinner shark (Carcharhinus brevipinna) litters from eastern Australian waters

Context The spinner shark (Carcharhinus brevipinna) is a medium-sized, coastal species distributed across the warm waters of all ocean basins. Knowledge of this species’ reproductive biology is limited to general parameters such as reproductive mode and average litter sizes, and very little is known about their reproductive strategy. Aims Here, we provide an assessment of multiple paternity, using single nucleotide polymorphisms. Methods DNA was extracted from 2 gravid females and the 18 pups between their 2 litters captured off the Australian eastern coast. Sibship analyses were conducted to assess multiple paternity. Key results For the first time globally, multiple paternity was confirmed in this species in both litters examined. Conclusions This study confirms that C. brevipinna employs some degree of polyandry as part of its mating system. Implications This research contributes to the growing number of studies regarding multiple paternity in elasmobranchs and provides new information on the reproductive biology of this species.