The giant Pacific octopus grows bigger and lives longer than any other octopus species. The size record is held by a specimen that was 30 feet (9.1 meters) across and weighed more than 600 pounds (272 kilograms). Averages are more like 16 feet (5 meters) and 110 lbs (50 kilograms). They live to be about four years old, with both males and females dying soon after breeding. Females live long enough to tend fastidiously to their eggs, but they do not eat during this months-long brooding period, and usually die soon afterwards. Giant Pacific octopuses have huge, bulbous heads and are generally reddish-brown in color. Like the other members of the octopus family, though, they use special pigment cells in their skin to change colors and textures, and can blend in with even the most intricately patterned corals, plants, and rocks. They hunt at night, surviving primarily on shrimp, clams, lobsters, and fish, but have been known to attack and eat sharks as well as birds, using their sharp, beaklike mouths to puncture and tear flesh. They range throughout the temperate waters of the Pacific, from southern California to Alaska, west to the Aleutian Islands and Japan. Highly intelligent creatures, giant Pacific octopuses have learned to open jars, mimic other octopuses, and solve mazes in lab tests. Their population numbers are unknown, and they do not currently appear on any lists of endangered or vulnerable animals. However, they are sensitive to environmental conditions and may be suffering from high pollution levels in their range.