Supplementary material from "Solitary humpback whales manufacture bubble-nets as tools to increase prey intake " ...

• Main Authors: Szabo, Andy, Bejder, Lars, Warick, Hunter, van Aswegen, Martin, Friedlaender, Ari, Goldbogen, Jeremy, Kendall-Bar, Jessica, Leunissen, Eva, Angot, Marie, Gough, Will
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: The Royal Society 2024
• Subjects: Ecology not elsewhere classified; Megaptera novaeangliae; Alaska
• Online Access: https://dx.doi.org/10.6084/m9.figshare.c.7408346; https://rs.figshare.com/collections/Supplementary_material_from_Solitary_humpback_whales_manufacture_bubble-nets_as_tools_to_increase_prey_intake_/7408346

Several animal species use tools for foraging; however, very few manufacture and/or modify those tools. Humpback whales, which manufacture bubble-net tools while foraging, are among these rare species. Using animal-borne tag and unoccupied aerial system technologies, we examine bubble-nets manufactured by solitary humpback whales (Megaptera novaeangliae) in Southeast Alaska while feeding on krill. We demonstrate that nets consist of internally-tangential rings and suggest that whales actively control the number of rings in a net, net size and depth, and the horizontal spacing between neighboring bubbles. We argue that whales regulate these net structural elements to increase per-lunge prey intake by, on average, seven-fold. We measured breath rate and swimming and lunge kinematics to show that the resulting increase in prey density does not increase energetic expenditure. Our results provide novel insight into how bubble-net tools manufactured by solitary foraging humpback whales act to increase foraging ...