Description of a collaborative sperm whale birth and shifts in coda vocal styles during key events

Key Points:

• On July 8, 2023, Project CETI documented the birth of a sperm whale calf (Unit A) off Dominica, observing 11 whales including 8 adults and 3 calves, with detailed video, audio, and behavioral data collected over 5 hours.
• The birth process lasted approximately 34 minutes from the emergence of the newborn’s flukes to completion, followed by intense social behaviors where adults lifted, pushed, and protected the newborn, including interactions with nearby short-finned pilot whales and Fraser’s dolphins.
• Acoustic analysis revealed a high density of specific sperm whale codas during the birth event, with notable changes in vocal style around key moments such as birth and interspecies interactions, supporting the role of vocalizations in social bonding and group coordination.
• The observed lifting behavior by multiple group members to support the negatively buoyant newborn is consistent with similar behaviors documented in other cetacean species and may have deep evolutionary origins dating back over 34 million years.
• The study provides rare, comprehensive insights into natural cetacean birth, highlighting complex social dynamics, interspecies interactions, and evolutionary adaptations that facilitate underwater births and newborn survival in sperm whales.