This video catches a rare glimpse of a gigantic, lunge-feeding blue whale deciding on what’s for lunch. A nonintrusive drone from Oregon State University quietly observed the world’s largest animal in the Southern Ocean off Australia. Cruising along at 6.7 mph—according to Leigh Torres of the Marine Mammal Institute at Oregon State, who led the expedition—it spots a worthy mass of krill and flips on its side, mouth wide open, to plow into its unlucky meal at 1.1 mph.
As for the second swarm of krill the whale encounters? It passes, thank you, confirming a behavior predicted by modeling: Blue whales bother to feed only when the payoff is likely to be worth the incredible amount of energy required to slow down their massive bodies and then return them to cruising speed. “It would be like me driving a car and braking every 100 yards, then accelerating again. Whales need to be choosy about when to apply the brakes to feed on a patch of krill,” Torres says in the video.