Because their upper and lower jaws are fused together, these fish must siphon food from the water using their tubular mouths like drinking straws. This group of 300 fish includes not only the 200 pipefish, but 5 ghost pipefish, 50 seahorses, 7 pipehorses, 12 shrimpfish relatives, 3 trumpetfish, and 4 cornetfish. The pipefish, seahorses and pipehorses exhibit the unique behavior that the females give the eggs to the male, and the males carry them until the young are hatched.