Water boatmen rest on the surface of the water sensing vibrations. If something is disturbing the water they will dive to investigate. When the boatmen get around one or two inches of their prey they can then track it using their eye sight. They kill the prey by jabbing it with its rostrum (feeding tube) and injecting its toxic saliva. They are very effective predators and can catch and eat tadpoles, small fish and even the fearsome larvae of the diving beetle. They will also eat flying insects that have accidentally fallen onto the surface of the water and can fly between different ponds.