Can some crabs swim?

What distinguishes this crab from, for example, beach crabs is that the outermost joint on the 5th pair of legs is shaped like a kind of flat oar. By moving these legs around like a propeller, they will then create a swimming movement that creates propulsion. They use this a lot when fleeing from predators that are trying to eat them, but also when finding food. They are also known to be voracious predators, so with the combination of being able to swim they can even catch small fish.