Bubble Net Feeding

Humpback Whales, Juneau, Alaska

This past summer, I was fortunate to revisit Alaska. For those of you who have never been there, add it to your bucket list and place it pretty high. Of all of the great memories I had there, our whale watch cruise was something I will always remember. The weather that day was quite miserable. The tour that we had signed up for started with a hike to Mendenhall Glacier and finished with the whale watch cruise. I was pretty excited as it was led by a local photographer and the boat we took was designed for photographers. The boat had windows that went outward and up, so that you could lean out of the window and have your camera stay dry. I've been on whale watches before, but not like this one. Shortly after we left, we found 13 humpback whales (at least that is what we counted) that were participating in a bubble net feeding. This feeding is unique to humpback whales but is only practiced by certain humpbacks in limited locations in the world. Bubble net feeding is a foraging behavior used to capture small schooling fish. Humpbacks have an elaborate way they use the bubbles to manipulate prey. The bubble blowing whale seems to know where the fish are because it changes depth of bubble deployment depending upon how deep the prey is positioned in the water. The process begins with the whales at the surface, diving as a group. Once the group is under water, one whale within the group initiates a series of vocalizations known as feeding calls. As the prey come close to the bubble wall, the bubble blowing whale encloses the wall of bubbles around them, creating a cylinder with the fish trapped inside. For more information click this link where you find an expanded description of the feeding.

This image shows four humpbacks starting their dive. The spray from other humpbacks can be seen in the background. I will further expand on the challenges of photographing this type of feeding in a later post. Suffice to say, it was quite an experience.