Harbor porpoises are shy, elusive sea mammals whose numbers are declining primarily because they are frequently caught by accident in commercial fishing nets. Specific numbers are unknown, but some scientists think their enormous range may mean that despite the declines, sizable populations could remain.

Harbor porpoises are found throughout the temperate coastal waters of the Northern Hemisphere. As their name suggests, they prefer the shallows, less than 500 feet deep, and are commonly seen in harbors and bays. They are also known to frequent inland waters, including rivers, estuaries, and tidal channels.

Harbor porpoises survive primarily on fish and are among the smallest of the cetaceans, reaching an average size of about 5 feet and 121 pounds. They can dive deep, more