Underwater Behavior of Southern Hemisphere Humpback Whales ( <scp> <i>Megaptera novaeangliae</i> </scp> ) Feeding in Super‐Groups, From Video Footage

ABSTRACT Large “super‐groups” of feeding humpback whales ( Megaptera novaeangliae ) have occurred regularly off the West Coast of South Africa since ca. 2011, but little is known about their feeding behavior. We used opportunistic underwater video footage to investigate near‐surface lunge feeding behavior, group coordination, and the use of pectoral fins in feeding. We analyzed 113 min of underwater video footage collected over 6 days. Whales passed through the frame on 623 occasions and were seen actively lunging on 182 occasions. No lateralization or coordinated foraging was observed. Gape cycles were short (mean mouth opening phase: 2.38 s and mouth closing: 1.69 s) with buccal pouch draining lasting the longest (15.61 s) and being a mostly passive action. The whales often surfaced while the pouch still contained water. Lunges and draining took place in all directions but mostly at ascending and even near vertical angles. Active flipper movements were observed during 81% of feeding lunges, providing further evidence that these uniquely large appendages are used hydrodynamically when feeding and may also play a role in prey herding. Disruption of feeding by diver presence was low. This study provides novel insight into the feeding behavior of Southern Hemisphere humpback whale super‐groups, and potential human‐whale interactions.