Amazing stuff!
"Many animals use tools to help snag their supper, from rock-wielding sea otters to crocodiles that use sticks as bait to lure nest-building birds. But only a handful of species—including crows, chimpanzees, and orangutans—can make and modify tools the way we humans do. Now, thanks to new research, this elite club may have a new member: the humpback whale.
Scientists have known for a while that these strapping cetaceans use their blowholes to release rings of bubbles underwater, creating specialized “bubble-nets” to herd, stun, and catch krill close to the ocean’s surface. According to a new study, however, solitary humpbacks in southeast Alaska don’t just make nets—they also manipulate them in sophisticated ways.
“These whales skillfully blow bubbles in patterns that form nets with internal rings, actively controlling details like the number of rings, the size and depth of the net, and the spacing between bubbles,” ..."
“These whales skillfully blow bubbles in patterns that form nets with internal rings, actively controlling details like the number of rings, the size and depth of the net, and the spacing between bubbles,” ..."
From the abstract:
"Several animal species use tools for foraging; however, very few manufacture and/or modify those tools. Humpback whales, which manufacture bubble-net tools while foraging, are among these rare species. Using animal-borne tag and unoccupied aerial system technologies, we examine bubble-nets manufactured by solitary humpback whales (Megaptera novaeangliae) in Southeast Alaska while feeding on krill. We demonstrate that the nets consist of internally tangential rings and suggest that whales actively control the number of rings in a net, net size and depth and the horizontal spacing between neighbouring bubbles. We argue that whales regulate these net structural elements to increase per-lunge prey intake by, on average, sevenfold. We measured breath rate and swimming and lunge kinematics to show that the resulting increase in prey density does not increase energetic expenditure. Our results provide a novel insight into how bubble-net tools manufactured by solitary foraging humpback whales act to increase foraging efficiency."
Figure 1. Variables and data collected from UAS and tagging methodologies.
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