Im01_©Christopher-Vaughan-Jones (IMAGE) Save Our Seas Foundation Caption The silky shark is classified as Vulnerable on the IUCN Red List of Threatened Species. The species shares all the classic traits that make sharks generally vulnerable to overexploitation, including a long gestation period before having a small litter of pups. Credit ©Christopher-Vaughan-Jones Usage Restrictions Credit must be given to the creator. Only noncommercial uses of the work are permitted. No derivatives or adaptations of the work are permitted. License CC BY-NC-ND Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.