Spyhopping is a behavior exhibited by cetaceans, such as the gray whale above, and some sharks. When an animal spyhops, it vertically pokes its head out of the water.

Most oceanographers say spyhopping simply lets the animals get a better view of activity near the water's surface. Sometimes, animals spyhop with their eyes above the water (as this whale is doing), and sometimes the animal's eyes are just below the surface.

Because the eyes of spyhopping cetaceans often remain underwater, some oceanographers think spyhopping may have more to do with a whale's hearing than its vision. Close to the surface, a gray whale like this one can better hear the waves near the surf line, which mark its migration route.

Whales and dolphins spyhop for long periods of time, up to 30 seconds. During this time, the cetaceans don't move their tail or flukes to remain upright. Instead, they use their pectoral flippers to keep them afloat, similar to a person treading water with their arms.

Some toothed cetaceans, such as killer whales, seem to use spyhopping to view prey, such as seals, swimming near the surface.

Baleen whales, like this one, often spyhop near whale-watching boats—demonstrating that they may be as curious about us as we are about them.

baleen
noun, plural noun

flexible, horn-like substance hanging from the upper jaw of certain whales, used to strain plankton from seawater when feeding.

behavior
Noun

anything an organism does involving action or response to stimulation.

cetacean
Noun

type of marine mammal, such as whales and dolphins, whose body is similar to a fish.

fluke
Noun

either half of the triangle-shaped end of a whale's tail.

killer whale
Noun

carnivorous whale, actually the world's largest species of dolphin. Also called an orca.

migration route
Noun

path followed by birds or other animals that migrate regularly.

oceanographer
Noun

person who studies the ocean.

pectoral flipper
Noun

limblike structures located on the side of the body of marine mammals.

prey
Noun

animal that is hunted and eaten by other animals.

spyhopping
Noun

behavior where an aquatic animal pokes its head vertically out of the water.

surf line
Noun

point in the ocean at which waves begin to break.

vertical
Noun

up-down direction, or at a right angle to Earth and the horizon.

wave
Noun

moving swell on the surface of water.