Bob Shadwick and the team from the University of British Columbia in Canada used a combination of skilfully attached hydrophones, pressure sensors and two-axis accelerometers on Blue Whales to record and track them.

This data was combined with a mathematical model to calculate the forces acting on the whales as they lunged. Then whaling literature and data from Blue Whale jaw bones in several natural history museums was used to establish the energy used versus the energy gained.

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