Dolphins Blast Into School of Fish

Dolphins and gannets blast through a shimmering, pulsing vortex of fish known as "prey balls" in these up-close glimpses of an underwater buffet.

In a prey ball, tens or hundreds of thousands of fish cluster into a dense swarm, moving as a single entity. It’s not clear if they’re getting into this shape to reduce their chances of being eaten, or because dolphins are herding them to be in that shape.

Dolphins circled clockwise around prey balls — dolphins appear, like most humans, to favor their right sides — skimming bites off the edges rather than plunging straight in. Often two dolphins would attack at the same time, rather than individually. When prey balls tried to dive, dolphins herded them back up.

Original article here.