Cheap gulp foraging of a giga-predator enables efficient exploitation of sparse prey.

• Main Authors: Videsen, Simone, Simon, Malene, Christiansen, Fredrik, Friedlaender, Ari, Goldbogen, Jeremy, Malte, Hans, Segre, Paolo, Wang, Tobias, Johnson, Mark, Madsen, Peter
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: eScholarship, University of California 2023
• Subjects: Animals; Biomechanical Phenomena; Feeding Behavior; Humpback Whale; Energy Metabolism; Food; Rorqual
• Online Access: https://escholarship.org/uc/item/1476k209

The giant rorqual whales are believed to have a massive food turnover driven by a high-intake lunge feeding style aptly described as the worlds largest biomechanical action. This high-drag feeding behavior is thought to limit dive times and constrain rorquals to target only the densest prey patches, making them vulnerable to disturbance and habitat change. Using biologging tags to estimate energy expenditure as a function of feeding rates on 23 humpback whales, we show that lunge feeding is energetically cheap. Such inexpensive foraging means that rorquals are flexible in the quality of prey patches they exploit and therefore more resilient to environmental fluctuations and disturbance. As a consequence, the food turnover and hence the ecological role of these marine giants have likely been overestimated.