“It is an awe-inspiring experience to be faced with a 3-metre-long, 500 kilogram predator, the size of a racehorse, as it launches itself out of the water and slides on its belly for a couple of seconds, coming to a halt barely a metre away from where I stood, without any barrier between me and it.”
That was how Erich Fitzgerald met Sabine the leopard seal.
Leopard seals are like the lions of the Antarctic. They are huge, powerful predators, known for their brutal killing strategy. They bite penguins and seal pups with their big canines, and thrash them onto the surface of the water to flay and dismember their prey.
But Fitzgerald, David Hocking and Alistair Evans have shown that these predators can take smaller prey in a very different way. They suck krill and small fish into their mouths and sieve them in the manner of whales, by passing their mouthfuls of water through tightly interlocking teeth. It’s astonishing behaviour that allows them to dine from the top and bottom of the food chain. As Fitzgerald told me: “This is equivalent to a lion hunting down zebras, but also regularly feasting on ants or termites.
I’ve written about the story for Nature News. Head over there for the full details.