The Harbour Porpoise is a small marine mammal found in coastal waters of the Northern Hemisphere. It typically measures about 5 to 6 feet in length and weighs between 110 to 150 pounds. This species is known for its rounded body, small dorsal fin, and dark gray coloration, which helps it blend into the ocean environment. Harbour porpoises primarily feed on fish and squid, using echolocation to locate their prey. They are social animals, often found in small groups, and are known for their shy behavior, making them less likely to breach the water compared to other cetaceans like dolphins.