Tuna are a saltwater finfish that belong to the tribe Thunnini, a sub-grouping of the mackerel family (Scombridae) – which together with the tunas, also includes the bonitos, mackerels, and Spanish mackerels.   There are fifteen species of Tuna ranging in size from the bullet tuna with a max. length of...

Tuna are a saltwater finfish that belong to the tribe Thunnini, a sub-grouping of the mackerel family (Scombridae) – which together with the tunas, also includes the bonitos, mackerels, and Spanish mackerels.   There are fifteen species of Tuna ranging in size from the bullet tuna with a max. length of 1.6 ft and weight of 4 lbs to the Atlantic bluefin tuna with a max. length 15 ft. and a weight 1,508 lbs.  The bluefin averages 6.6 ft and is believed to live for up to 50 years.  An active and agile predator, the tuna has a sleek, streamlined body, and is among the fastest-swimming pelagic fish with capable speeds of almost 50 mph.