I recently attended a talk by a friend who has climbed the highest peaks of all seven continents, hung out with lowland gorillas, and watched birds in Madagascar. Yet when he described whales bubble feeding in Antarctica, you could hear the wonderment in his voice. That inspired me to write about humpback whales.
When bubble feeding, as shown in this video, humpback whales dive deep before circling and releasing air to create columns of bubbles. These towering bubble cylinders corral fish into tight schools because they see the bubbles as a barrier. Sensing a threat, the fish instinctively form tight, swirling groups. The whales then just have to open their mouths and come up through the center of the ring of bubbles to capture the fish.
Humpback whales have inspired at least two biomimetic inventions. Perhaps the best known is the tubercle technology used in industrial fans and wind turbine blades that mimic their fins. For a bus-sized animal to circle tightly in water takes a lot of agility, and the bumps or tubercles on the leading edges of their fins reduce drag and create lift to help them make those tight turns. Tubercle technology applied to industrial fans increases air movement with less energy expended, fewer blades required, and less noise. When applied to wind turbines, the technology reduces the wind speed needed to generate power and reduces noise.
The bubble nets created by the feeding whales inspired a way of fishing that could greatly reduce by-catch—the capture and, unfortunately, sometimes death of non-target fish, turtles, whales, and dolphins. The Instituto Politécnico de Leiria in Portugal has prototyped a technology that uses a system to create an underwater wall of bubbles. This would eliminate the need for nets, which are the main cause of by-catch.
Biomimicry is the conscious emulation of life’s strategies. It takes looking at nature with a sense of wonder like that of my friend. It takes a willingness to ask questions and then seek out answers to those questions. How does an organism do that? Why does it do it? What can I learn from it to design something that is better than the way we currently do things? Nature has a lot to teach us; we just need to open our minds to the possibilities.