Who is The Commander? He’s onne of many species of crayfish that live in St. Martin’s streams and, we predict, the breakout star of the upcoming exhibit “Gut Life: The Fascinating Freshwater Ecosystems of St. Martin” at Amuseum Naturalis. The largest species of crayfish are considered the top predators in their ecosystem, and we can certainly attest that the Commander is the apex predator of the Amuseum’s freshwater aquarium. The Commander enjoys intimidating others, cleaning his giant claw, and ruthlessly killing and eating anything smaller than him, including other crayfish.