Scientists at the University of Hawaiʻi at Mānoa, along with their collaborators, have captured a unique thing: A humpback whale swimming in a circular pattern while blowing bubbles to create a net to encircle its prey. They captured the footage in an attempt to know how these animals are manipulating their prey and preparing the prey for capture.
Scientists used cameras and sensors attached to the whales with suction cups, coupled with drones, to capture this usual event in the cold blue-green waters of Southeast Alaska. Through this footage, scientists gain an understanding of how humpback whales in Alaska feed and how some whales use bubbles to optimize their consumption of krill by producing bubble-nets.
The video and accelerometer information combined with the drone, are giving bits of knowledge into the fine-scale details of how the whales complete this conduct and how frequently they should do this to put on enough vitality and weight before they migrate down to Hawaiʻi to breed and mate.
Lars Bejder, director of the UH Mānoa Marine Mammal Research Program (MMRP) said, “We have two angles. The drone’s perspective is showing us these bubble nets and how the bubbles are starting to come to the surface and how the animals come up through the bubble net as they surface, while the cameras on the whales are showing us the animal’s perspective. So overlaying these two data sets is quite exciting.”
“About 3,000 humpback whales visit Alaska during the summer feeding period, and up to 10,000 are in Hawaiʻi for the winter breeding period. When the whales leave their foraging grounds and migrate 3,000 miles, they stop eating until their return several months later. Females in Hawaiʻi are using large amounts of energy when they give birth, lactate, and raise their offspring before migrating back to their foraging grounds.”