How Humpback Whales Use Their Flippers And Bubble Nets To Catch Fish

As large aquatic mammals that have a lot of body mass and an equally large appetite, humpback whales (like most whales) need to eat a lot everyday. In fact, according to a recent study made by scientists, some even snag huge mouthfuls of fish by using their flippers.

This tactic is called pectoral herding, and according to scientists who conducted the study, humpback whales (Megaptera novaengaline) found off of the coast of Alaska has been observed with this ability. Per the report, which was published in Royal Society Open Science Wednesday, this counts as the first time that this behavior has been observed in detail, let alone recorded.

That’s because usually, humpback whales catch fish to feed by lunging with their mouths open, similar to most species of whales. In some occasions, they also swim in an upward spiral to create a bubble net, which makes it harder for the fish to escape, therefore making it easier for them to feed. However, living underwater means that there is much more unobserved behavior that these animals exhibit.

"But there’s so much you can’t see while you’re looking at these animals, standing on a boat," Madison Kosma, a whale biologist at the University of Alaska Fairbanks, said.

To learn more about their feeding behavior, scientists and whale biologists flew a drone to get a better view of them. In other times, they also used a video camera attached to a pole that’s connected to the walkways of floating salmon hatcheries. This study was then made over the course of three years (2016-2018).

From the gathered data, scientists observed that two whales kept using their flippers to take in fish. Furthermore, there were also instances that the whales tilted their flippers to reflect sunlight underwater, which then disorients fish and makes them easier to catch. The whales also guided fish into their mouth by making a bubble net and ascending upwards with their flippers outward.

Although newly observed, the scientists who created the study stated that the behavior isn’t a fluke, and is most likely done by other whales as well.

whale Pictured: A whale jumping out of the water. Photo courtesy of Kate Stafford/Cell Reports 2015