Sawfish, any of a family (Pristidae) of sharklike fish having “saws” of cartilage set with 2 rows of teeth on their snouts. Sawfish are found in all warm seas and may swim up rivers. The common sawfish of the Gulf of Mexico swims up the Mississippi. Sawfish can grow up to 30 ft (9 m) in length. They use the saw to dig up shellfish or to kill small fish. Although they are reported to be docile, fishers treat them with considerable respect.