To behold the pirouettes and arabesques of whales underwater is a lot like watching the Russian ballet. Few creatures are as elegant—and formidable—as a humpback whale on the move.
Most of us will never get to see the deadly dance of humpback whales in person, but some incredible new footage captured by Alaska Strike Zone Sportfishing offers us a glimpse at the cetacean's most curious hunting technique: the bubble-net.
Those tiny blips you're seeing at the surface of the water indicate something much more imposing down below. What the lucky cameraman managed to witness was a humpback's shoreline feeding performance. Bubble-net hunting, as far as biologists know, is unique to humpback whales. The method creates a literal air bubble cage for their meal, in this case herring, which allows the whales to more easily snap up small fish and krill.
Humpback whales have been observed diving 150 feet below a shoal of prey and forcing it to the surface amid a circle of bubbles. Since humpbacks are baleen whales, they'll gulp down entire mouthfuls of water by expanding a set of 14 to 35 long throat pleats—critters included—and sift out their food through baleen filters made of stiff keratin.
However, the mechanisms behind bubble-net hunting weren't entirely known to scientists until a few years ago. In 2011, David Wiley, a marine biologist with the National Oceanic and Atmospheric Administration outfitted several whales with digital suction cup tags that measured pitch, roll, heading, depth, and sound. The data that was returned provided the first-ever 3D depiction of underwater bubble-net feeding.
What Wiley saw was a snapshot of complex choreography and teamwork that he likened to sophisticated tool use among apes. In order to create a swarm of bubbles, the whales would swim in upward spirals, exhibiting a previously unknown behavior called "double-loops." Usually working in groups of two or more, humpbacks spiraled toward the surface and slapped their flukes on the ocean's surface. Once their prey were successfully corralled at the top of the water, a final lunge would be deployed to funnel the school of small fish or plankton into their gaping mouths.
A later study, published in the journal Science, found evidence to support the notion that various bubble-net fishing techniques are passed down from generation to generation among regional humpback whale groups. By analyzing a database of 27 years of humpback foraging behavior, biologists were able to model the likelihood that techniques were learned through peer-to-peer socialization, rather than genetically preprogrammed. The models provided quantitative proof that humpbacks socially learn new behaviors, and actually share traditions or quirks with one another.
Humpback whales, like the one shown in the video, can be found in Alaska's frigid waters during the spring, summer, and fall. During the winter, they'll migrate to warmer breeding grounds in the North Pacific.
Alaska's migratory humpbacks are currently a point of contention for many environmentalists who wish to see the species kept on the Endangered Species List, and corporations and residents invested in offshore oil extraction in the middle of the whale's critical habitat. While delisting the humpback whale won't necessarily remove all of its protections, the move could prevent it from being covered under laws and regulations that guard against the threats of climate change and habitat disruption.
It's easy to see why the mighty humpback inspires so many people to want to protect it. The whale's astounding size, grace, and remarkable intelligence seem to defy the laws of terrestrial life. Seeing them reminds us of an era when larger, fiercer creatures ruled the deep, but this time, let's hope the ocean's current megafauna stick around for perpetuity.