In addition to shellfish, bony fish such as the perch make tasty meals as well. The perch has six different fins that all serve different purposes. The two pairs of pelvic and pectoral fins enable the perch to steer and brake. It takes in and excretes gases via the water that passes over its gills. The perch has a swim bladder that allows it to change depths in the water by pumping carbon dioxide, oxygen, and nitrogen found in the blood in and out of the swim bladder.
Perches become mature adults at the age of two or three years.
Osteichthyes is the salmon . The body structure of the salmon is similar to that of the perch. Salmon travel approximately 900 miles upriver and climb to elevations of 6,500 feet to arrive at their natal spawning grounds. Northwest salmon, found off the coast of Northern California to the Gulf of Alaska, spend approximately two years in the ocean before returning to freshwater to spawn. The information used in constructing this webpage was found in Prentice-Hall Biology .