Humpback whale mother and calf (IMAGE) University of California - Santa Cruz Caption Humpback whale mother and calf in Antarctica. Research shows reduced krill supplies lead to fewer pregnancies in humpback whales. Credit © Duke University Marine Robotics and Remote Sensing Lab Usage Restrictions For use only with news coverage of this research License Original content 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.