Humpback Bubbles

Today in class one of the groups discussed the bubble net fishing method of the humpback whale. Previously, I had never heard of this bubble feeding. I found it very interesting and unique and decided to do a little research of my own. On the left I have an image of a whale creating a bubble net. As the whale swims upwards, it slowly begins to spiral. While doing this it blows bubbles creating a bubble net that is free of bubbles in the middle. The fish, afraid of the disorienting bubbles, remain within the calm centre of the net. Finally, the whale swims up through the net with its mouth open, which is know as "lunge feeding" and swallows the fish that are swarmed in the middle. Apparently, as mentioned in class, other whales help to blow bubbles on the net to intensify the bubble wall, and more make loud noises to further disorient the fish. This is also a cue for all of the whales to be ready to lunge at the same time. Furthermore, accoustics in water reacts differently with bubbles compared to bubble free water. The bubbles keep much of the sound within the net (the bubbles act as a sort of barrier), which allows for more efficient disorienting of the prey in terms of noise. On the top is a photograph of the bubble net as seen from the surface. I found this all very interesting, the way the whales work together in order to all get a nice lunch.