Ever wondered how blue whales go about deciding what to eat? It isn’t as easy as it sounds. For blue whales, every lunge to feed has to be worth the effort, given that it is essentially a very energy-intensive act. New footage from Oregon State University captured with the help of a drone offers a stunning view of the entire process.

Leigh Torres, an assistant professor at the university, mentions in the video (above) that going in for a feed requires the whale to turn on its sides and lunge up to swallow its prey.

After feeding, it has to expend some energy in order to get back to a decent cruising speed, since opening its mouth slows it down. To eat or not to eat is a hard choice that the magnificent creatures make very quickly, as demonstrated in the video where you observe a whale moving towards a krill patch before changing its mind at the last minute to modify its course.

Earlier, in September 2016, Stanford researchers managed to get perspectives from the whales by attaching suction cup cameras and observed their viewpoint as they swooped in for a meal.