Bluefin tuna are a species of three different fish found throughout the Atlantic Ocean, the Mediterranean, and the Gulf of Mexico.
The body of the bluefin tuna typically varies in shades of blue with flecks of white, and a silverish-white or blue-ish grey underbelly. Their tail fins are dark blue, sometimes with a splash of grey, and the second dorsal fin is usually grey but with some yellow hues.
It is these yellow tones in the second dorsal fin which usually gets them confused with their close relative, the yellowfin tuna.
Bluefin Tuna Species
Tuna is a variant of saltwater fish belonging to the tribe Thunnini, a subgroup of the mackerel family.
Among the Thunnini are 15 different varieties of tuna varying in size and shape and are further subcategorized into “true tuna” species such as yellowfin group and bluefin group.
Some pundits determine that there are three main species of bluefin tuna – Atlantic, Pacific, and Southern.
Other experts suggest that there are five different classifications, adding Bigeye and Longfin tuna to the bluefin category.
Of the species, the Atlantic is undisputedly the largest and, along with the Pacific bluefin, is the most popular among bluefin tuna.
Although they are warm-blooded, bluefin tuna thrive in cooler waters.
Size And Appearance
At first glance, bluefin tuna is similar in shape and appearance to other varieties of tuna, so it is oftentimes difficult to differentiate them from others such as the yellowfin tuna. The most notable difference is in their size.
Bluefin tuna are among the largest types of tuna with an average weight between 60 and 245 kgs (130 to 300 lbs) and an average length between 1.0 and 2.0 meters (3.3 feet to 6.6 feet).
The Atlantic variety can weigh up to 1,500 pounds (680 kg). This is about a similar size to the marlin and swordfish.
Their bodies are designed to move rapidly in water, and they are the fastest among their species. Considered football or torpedo-shaped, they are built for endurance and speed as predatory creatures.
The body of the bluefin tuna is mostly dark blue to match their dark blue tail fins, and the underbelly is usually some variation of silver or blue-grey.
The short pectoral fin does not reach past the second dorsal fin, which is a colorful grey and yellow.
The vibrant colors are not only beautiful to look at but they also offer practicality for the bluefin by providing much-needed disguise from predators below as well as above the water.
Sadly, they tend to lose some of their vibrant color once they are caught.
Bluefin Tuna Allure
Bluefin tuna is more than just a seafood option; it provides also food as well as income for a great many people.
It carries significant prestige as the most expensive fish and is a common feature in sophisticated seafood dishes. An Atlantic bluefin was reportedly sold for close to $2 million in Asia.
Bluefin tuna meat is of excellent quality and is a tasty fish that has a high-fat content. It is one of the types of fish that is safe to consume without cooking. This makes it ideal for use in Japanese raw food cuisines such as sushi and sashimi.
Otoro is a specialty type of sushi made from the underbelly of the bluefin, which is the most expensive part of the fish.
Anglers and sport fishermen alike find the bluefin tuna attractive as they can hardly resist the allure and bragging rights they would no doubt earn by catching one of the largest and most high-priced fish.
Due to their high value, and as a consequence of overfishing either recreationally or to provide food, bluefin tuna are currently an endangered species.
More specifically, the International Union for Conservation of Nature (IUCN) has classified the Southern bluefin tuna and the Atlantic bluefin tuna into critically endangered and endangered categories respectively. There is a danger that they could very soon become extinct.
Bluefin tuna heavily contribute to the balance of the marine ecosystem so their importance cannot be underestimated.
To crackdown on illegal fishing, international regulations and conservation efforts have been introduced in order to preserve the bluefin tuna and to protect their natural environment.