They don’t have the same incredible sense of smell and ability to sense electrical activity of nearby prey that sharks have. They don’t have the phenomenal eyesight of mantis shrimps, which can see far more colors than humans can. And they don’t use echolocation like dolphins and whales. So what secret weapon do seals use to find their prey in the dark waters of the sea? The answer might tickle your fancy: it’s their whiskers!
While humans can’t move their facial hair, most mammals with whiskers can move them, and vibrations of these whiskers help the seals collect information about their surroundings. Elephant seals have the highest number of nerve fibers per whisker of any mammal, so they were an ideal choice for studying the role whiskers play in hunting. In an experiment, researchers placed video cameras on female northern elephant seals and observed what happened as they went hunting. The findings confirmed that seals’ whiskers are a key tool in helping them find dinner.
The cameras the seals wore emitted an infrared LED light that the seals couldn’t see but which could pick up the movement of their whiskers as they neared prey. Scientists learned that elephant seals extend their whiskers beyond their mouth and rhythmically move them forward and backward to feel for movement in the water which might come from the wake of a swimming fish. This whisker movement also helps during a chase, giving seals the information they need to sense precisely where the prospective meal is. Though seals use other cues in hunting, such as tracking other animals’ bioluminescence, it turns out that their whiskers are the most important tool they use to find food.