The yellowtail amberjack, or Japanese amberjack, is a yellow-tailed food fish found in the warm, subtropical waters of the Indo-Pacific, Eastern Pacific, and Southern Atlantic seas. The Japanese amberjack is farmed in the inland seas of Japan, where its flesh is prized for sushi. In fact, these fish are considered valuable game fish throughout the world.
The Japanese amberjack is usually easy to identify by its distinctive markings. These fish may have an olive-green to blue upper back, often bearing yellow spots. A yellowish stripe may run down the length of the body, and smaller yellow stripes may run the length of the lower sides and belly. The caudal fin is usually bright yellow, and the dorsal fin may bear a yellow tint as well.
These prized food fish may grow to a length of 8.2 feet (about 2.4 m), though a more typical length is about 2.6 feet (0.79 m). They may weigh up to 213 pounds (96.8 kg), though they're usually much smaller. On average, yellowtail amberjacks found in the Pacific and off the Gulf Coast weigh between 50 and 110 pounds (22.6 to 49.9 kg). A yellowtail amberjack weighing 115 pounds (52.2 kg) and measuring 66.5 inches (168.9 cm) long was caught off the coast of Texas in 1994.
Thriving in the waters of the Indo-Pacific sea off the coasts of India, Japan, and Australia, the yellow amberjack can be found in almost any tropical or subtropical ocean waters. It can also be found off the coasts of Baja California, and in the Gulf of Mexico. They can even live in the Atlantic waters off the coast of Africa.
These fish typically live alone or in small schools. They generally prefer shallow water, and can usually be found no more than 250 feet (76 meters) from the surface. Adult fish are most often found near shorelines, coasts and reefs. Juveniles may venture beyond the continental shelf. The yellowtail amberjack usually prefers to live in warm water, seeking temperatures between 64 and 75°F (18 to 24°C). They normally subsist on small crustaceans, fish and squid.
Adult yellowtail amberjacks typically lead a solitary existence, while the juveniles are more likely to form schools. Females of the species typically liver longer than the males, with lifespans of up to 15 years. They can begin to spawn at about two to three years of age. Spawning normally occurs in midsummer, offshore.