Tuna is one of the most popular saltwater fish globally, comprising $149.1 million in revenue in commercial landings alone.
The most fished ones are skipjack, yellowfin, bigeye, and albacore, but there are many more we will cover here. The main thing to know about tuna is that they are not a specific fish but rather a “tribe” of fish.
They have distinguishing features to tell them apart, so read on as we break down the various types of tuna you might encounter.
Of the different types of tuna, bluefin is one of the most famous, being prized both for recreational fishing and food.
Bluefin tuna are found throughout the Atlantic and Pacific Oceans and are around 5 feet long and 130 pounds, but they can get much larger, some over 1000 pounds.
On the outside, bluefin tuna are metallic blue and silver and have yellow-green fins. Compared to different kinds of tuna, bluefin tuna are a bit squat and have subtle white striations.
They are most commonly confused with yellowfin, but the main difference is that bluefins have a blue-green lateral line running down the sides of their body.
Despite their similar name, blackfin tuna is a much smaller variety of tuna than bluefin, reaching a maximum length of 40 inches and an average weight of 50 pounds, though most often, they are a mere 20 inches and 10 pounds.
They can be found in the waters of the Atlantic Ocean, ranging from Martha’s Vineyard to southern Brazil, but they are most popular in South Florida and the Caribbean.
Physically, they look like torpedoes, with black stripes running across their bodies, silver bodies, bronze-colored fins, crescent-shaped tailfins, and compact scales over the entirety of their bodies.
Yellowfin, which inhabits tropical and subtropical oceans around the world, is another popular type of tuna.
They are also commonly called “ahi,” though technically, the term most accurately names the bigeye tuna (another entry on this list).
As their name suggests, yellowfin tuna are most identifiable by the radiant, almost neon yellow of their tail fins, their pronounced dorsal fins, and the stripe running down their bodies.
This stripe stands out strikingly against their silver underbellies and blue tops. They can be between 40 and 80 inches and weigh between 300 and 400 pounds.
Closely related to yellowfin, bigeye tuna is a species that lives in tropical and warm waters in the Atlantic and Pacific Oceans, though not in the Mediterranean Sea. Like the yellowfin tuna, bigeye tuna are mid-sized, reaching over 5.5 feet and around 250 pounds.
Bigeye tuna are recognizable from their streamlined build and the dark blue color on their backs and sides, and for their namesake eye, which is large and bulging like a googly eye.
Due to environmental changes, bigeye tuna have become increasingly rare, making it progressively less likely to encounter one on a fishing trip.
Albacore tuna is one of the most-fished tuna in the world. In the United States alone, around 872,000 pounds of albacore is landed each year, and internationally, albacore is a major export product from various Pacific island nations.
Albacore habitats are spread out throughout the world, and they can be found in the Atlantic, Pacific, and Indian Oceans, as well as the Mediterranean Sea.
They can measure up to 50+ inches in length and 100 pounds in weight, although they more commonly grow up to 35 inches long and 20 pounds. They’re noteworthy for their silvery-blue coloring and their extremely long pectoral fins.
Despite its similar name, black skipjack is more closely related to mackerel and little tunny tuna than to skipjack tuna themselves.
They inhabit the warm waters of the Pacific coastline, especially from California to Peru, and are most abundant in the waters nearest to the equator – namely Ecuador, the Pacific Coast of Colombia, and the Galapagos.
Black skipjack is dark blue, not black, though their 13-15 spinal spikes are very dark in color. They can be mistaken with close genetic relatives like the bonito, though their namesake black stripes can distinguish them for anglers.
Not to be confused with the dogfish, a sub-family of sharks, dogtooth is a variety of tuna found in the temperate waters of the tropical and subtropical Indian and Pacific Oceans.
However, they can also be found in areas of the Red Sea, Papua New Guinea, and the Marshall Islands.
Dogtooth tuna are most notable for having no scales except for the area around their corselet. Additionally, they can be recognized by their large, cone-shaped teeth, which look similar to those of a dog (the source of the dogfish’s name).
Technically, bonitos do not belong to the Thunnini tribe (the “true” tuna family), but rather is its own tribe, Sardini (which, itself, is unrelated to the sardine fish).
However, they belong to the same family as tuna and mackerel and share physical resemblances with them.
They can also be found in the Atlantic Ocean, Pacific Ocean, the Mediterranean Sea, and the Black Sea.
Most notably, bonitos are noteworthy for the stripes that run down their bodies, which, depending on the type of bonito, can be black or blue and intermingled with green, silver, or even copper.
They resemble tuna in their body shape, though they are narrower, growing up to 30 inches in length and 12 pounds in weight.
The kawakawa tuna is a species found in the Indian and Pacific Oceans, with its habitat stretching from the Red Sea to the Polynesian Islands in the West Pacific, though the fish can stray into the central pacific.
Visually, kawakawa tuna have dark blue or blue-green skin with silver bellies, as well as thick, complex stripes around their dorsal fins.
There may also be dark spots around their pectoral fins, although these do not occur in all kawakawa. The species grows to about 23 inches in length but can reach a maximum size of 40 inches and 30 pounds.
Longtail, also called the northern bluefin tuna in Australia, is another native species of the Indo-West-Pacific, preferring warm tropical waters.
A member of the Thunnus (Neothunnus) subgenus, longtail are related to “true tuna” like the bigeye, albacore, and bluefin, but close to blackfin and yellowfin.
Longtail can be recognized by the silvery-white color of their bellies and the dark-colored area around their dorsal fins.
Their fins can range in colors from silver and gray to yellow and green. They can reach 57 inches in length and 80 pounds in length, though they are more commonly around 35 inches 28 pounds.
Like the kawakawa, mackerel, and black skipjack, this tuna is a member of the tribe Thunnini but not the genus Thunnus, meaning it is not a “true tuna.”
That semantic issue, however, has not dampened the little tunny’s profile: it is the most common species of Tuna in the Atlantic, ranging from Brazil to New England to the Mediterranean.
As its adorable name suggests, it is one of the smallest members of the tuna family. Its average size is 32 inches and 20 pounds, but larger specimens can grow up to 48 inches and 35 pounds.
Its body is silvery near its belly and green-blue near its dorsal fins, with a set of undulating black stripes in the latter area that resemble the marbling on a geode.
Skipjack tuna is one of the most popular types of tuna throughout the world, representing a major fraction of tuna fisheries’ take.
Its habitats range throughout the Atlantic, Pacific, and Indian Ocean waters, particularly offshore tropical and subtropical waters.
Visually, it isn’t the most bombastic member of the tuna family, but it’s still relatively easy to recognize.
It has a round, elongated body that is mostly without scales, and its color is a very dark blue that can sometimes appear purple.
Its most distinguishing element is the set of long, very dark bands of color that stretch across its body.
As you can see, many different kinds of tuna inhabit the world’s oceans. They all have their preferred habitats and distinct features as well as rarities and values, so it is essential to know the differences between them.
So whether you are a novice angler or a veteran of the high seas, we hope that our list has helped you learn more about different types of tuna, where to find them, and how to distinguish them.