The yellowtail is a type of fish closely related to the jack. They have a similar color and body shape, but they are slightly different in diet and behavior. The yellowtail is much more common than the jack and can be spotted easily. The Japanese amberjack or yellowtail is a species of Jackfish in the jack family Carangidae. It can be found natively throughout the Northwest Pacific Ocean long distance from Korea to Hawaii and even as far away as Japan, where they like hanging around near rocks by coastlines year round!