Porbeagle Shark

The porbeagle is a stout shark that is blue-gray on top and white underneath with a white patch on the trailing edge of the first dorsal fin. It has a crescent shaped tail and a secondary keel that effectively cuts the water during the side to side swimming motion. Adults can attain a size of 3.7 meters (12 feet), and have an average life expectancy of 30 to 40 years. This shark has relatively large eyes. The teeth in the moderately sized mouth are similar in both the upper and lower jaw (they are smooth-edged with lateral denticles), although young individuals may lack the lateral denticles.
The porbeagle has a heat regulating mechanism that raises the body temperature 2.7 to 8.3 degrees Celsius above the surrounding water temperature. This allows the shark to operate more efficiently in the cooler waters it inhabits. Unlike many other sharks the porbeagle must swim at all times in order to breathe.
The porbeagle shark is common in pelagic and littoral zones, and inhabits water down to a depth of 370 meters (1,120 feet). It is most commonly found on continental shelves or inshore. It prefers cool waters and is usually found in temperatures below 14 degrees Celsius.