By Kathleen Berger
Executive Producer, Science & Technology
Blue whales are among the largest creatures to have ever lived on Earth. They can grow to 100 feet long and weigh more than 150 tons.
“They are bigger than any dinosaurs you can think of,” said Jean Potvin, PhD, professor of physics at Saint Louis University.
Potvin is part of a team of 17 scientists who investigated swimming habits of blue whales and humpback whales in the wild. They used electronic tags and drones off the coast of California. In Monterey Bay, the scientists tagged blue whales using suction cup tags equipped with sensors and cameras. The digital tags were later recovered from the water after floating to the surface when biologists received the signal.
Biologists on the boat flew drones that also had sensors and cameras to make size assessments of whales.
At Saint Louis University, Potvin studies the biomechanics of swimming. He’s interested in the swimming performance of whales and the mechanics of how whales feed.
The digital tags measured the speeds and accelerations performed by whales, as well as recorded video of the maneuvers and their encounters with prey.
“Correlating all of this performance data, with body size, is one of the major goals of this study,” said Potvin.
The National Science Foundation funded the project’s $800,000 grant involving three universities to include Potvin’s team at SLU and research teams from Stanford University and West Chester University.
With new data from the tags, Potvin can carry out computational fluid dynamics simulations. The simulations help scientists study biomechanics of swimming as whales capture prey; avoid predators and obstacles; and compete for mates.
“We’re talking about swim speeds, roll rates and turning radius supported with computer simulation of the water that flows by the whale,” he said.
The team is designing computer software for whale research. The research group generated data through computer simulations aided with subscale whale figures from 3D modeling by using a 3D scanner.
“Once we have this piece of software, then we can ask other questions. How much energy does a whale need to live? How much energy does a whale need to swim? And how much energy does a whale need to eat?”
Potvin said improving whale research would promote a better understanding about the evolution of whales and what the future may hold.
“Why or how is it that whales got so big and how much bigger can they be? You can use the software, for example, to change the size of a whale and to change the size of its flippers and see how that affects maneuverability. But at some point, maneuverability decreases so much that the whale has really limited possibilities for feeding. Think of the blue whale. The blue whale is so big it can’t go after fish anymore. Blue whales feed exclusively on krill, which is a less mobile prey.”
The hope of the research is to help with conservation needs and management of resources worldwide to help the survival of whales.