HAIN ET AL.: FEEDING BEHAVIOR OF HUMPBACK WHALE 



Figure 4.— Aerial views of bubble net construction by a humpback whale. A through E are 5 frames from a 29-frame sequence; F is 

 from a sequence immediately following. Underwater exhalations are used to form a bubble net approximately 15 m in diameter, 

 composed of some 15 individual bubble columns. Arrows in B indicate undersides of left pectoral fin and flukes. In A through C, 

 whale is rotated on its longitudinal axis so that the blowhole and dorsal surface are toward the center of the circle. In D, whale turns 

 sharply about on the right pectoral fin and prepares to pass through the center of the net. A stream of turbulence is seen trailing from 

 the dorsal fin area, which is being sharply thrust to the whale's left. In E, the whale is seen in feeding posture, mouth agape, under- 

 water in the center of the net. In F, the whale surfaces and blows weakly before exiting the area of the net. Photographs by S. Kraus. 



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