Tuna sandwiches. Tuna salad. Tuna casserole. Tuna sushi. Tuna is one of the most popular foods in the world. It is used as a condiment in numerous dishes and is often eaten on its own.
If you are like most people, you have mostly seen tuna that comes in a can. But even this tuna product is more diverse and varied than you might imagine.
Most people cannot tell one type of tuna from another. This is unfortunate because there are so many different types of tuna, and each type of tuna has its own distinct characteristics. You should not continue through life blind to the subtleties of tuna fish.
It is high time you get a tuna education. This is a great place to start.
Taking an interest in tuna is not a futile, frivolous, or uninteresting endeavor. There is much to learn about this wily white fish. Nearly every type of tuna is made into a food product.
Whether you are planning a large party and want to know your options or want to know more about the origins of the kinds of food you are putting into your body, this article will give basic insight into tuna.
The Tuna Fish in General
Although there are different types of tuna fish, they all share a few distinctive characteristics. The physiology of the tuna fish respiratory system makes it necessary for them to swim constantly so that water constantly passes through their gills.
This persistent swimming also oxygenates their blood, giving them the ability to generate heat and regulate their body temperatures. This gives them the capacity to tolerate a wide range of water temperatures.
The upshot of such thermo-self-regulation is that the tuna fish is a highly migratory animal. They are found in all the world’s oceans. They are good at adapting and surviving and are thus not as easily depleted as other types of fish.
Types of Tuna
The tuna should not be thought of as a family of fish. They should instead be viewed as a big nation that is split into two tribes: the Thunnini and Sardini. The Thunnini consist of albacore, skipjack, blackfin, little tunny, yellowfin, and all three species of bluefin. The Sardini includes the dogfish tuna and smaller bonitos.
They have the longest pectoral fins of any tuna, which is the most distinguishing quality of the albacore. The latter is found throughout the Pacific Ocean, but the largest schools of them are found off the coasts of California, Oregon, Washington, and British Columbia.
Albacore is known as the chicken of the sea owing to their white-colored flesh. Most of the canned tuna found in American grocery stores is albacore.
The bigeye is often confused with the yellowfin. But the former has a noticeably larger eye than the latter. Bigeye tuna are found in the Atlantic and Pacific oceans. These are big fish. They can grow to more than 7 feet and weigh as much as 400 pounds.
They are the babies—the smallest—of the Thunnini tribe. Blackfin tuna are on average 3 feet in length and less than 50 pounds in weight. They are found mostly throughout the western Atlantic, which stretches from the Bay of Boston to the northeast continental shelf of Brazil.
The Blackfin is oval-shaped with dark coloring along the top. They are energetic and vigorous and put up quite a fight when caught.
The bluefin is another monster of a fish. They can weigh more than 1,000 pounds and stretch out more than a dozen feet. The bluefin is a prized gamefish, especially in Japan where they are used to make dishes that command extremely high prices. Atlantic bluefin tuna is also in high demand.
The bonito is marked by its long thin body with striped lines down the back. They are small fish in that they rarely grow more than a foot long and weigh not much more than 12 pounds. Bonito tuna is found in the Atlantic and the Pacific. There are slight differences in size and coloration between the bonitos found in the two oceans.
This is another type of tuna that is distinguished for its white flesh. It is also another big fish. The dogtooth can grow as long as 6 feet and as heavy as 250 pounds. They are also deep divers, having been found at depths of 900 feet. They are found in the Indo-Pacific area.
7. Little Tunny
Also known as false albacore, the little tunny are, well, little. They do not grow much more than 2 feet long and can weigh less than 30 pounds. They are recognizable by the black pattern along their backs. The little tunny is found in the Atlantic and Pacific, but the highest population is found in the northwest Atlantic.
The skipjack gets its name from its behavior. It likes to skip and jump across the surface of the ocean. These tuna fish are distinguished by the dark lines on their bellies. They are another of the baby tunas, weighing less than 60 pounds and growing little more than 3 feet long. Skipjack tuna are found throughout the Pacific and Atlantic oceans.
One look at this tuna fish and you will know how it got its name.
The yellowfin is found in the Pacific, Atlantic, and Indian oceans. They swim in schools and are often very large fish, getting up to 6 feet in length and 200 pounds in weight. The highest concentration of yellowfin tuna is in the western Pacific near Thailand and the Philippines.
Tuna as Food
Tuna fish are mostly used by their human-animal cousins as food. Tuna is offered in supermarkets as canned products, frozen whole fish, tuna steaks, and catch-of-the-day specials. You will also find a variety of tuna dishes served in delis and restaurants. Sushi restaurants offer perhaps the widest variety of tuna delicacies found anywhere.
Skipjack, yellowfin, and albacore are known as light tuna and are the least expensive. What is known as “sushi grade” tuna fish are the most expensive? These include bluefin and bigeye tuna.
Is tuna tasty?
The short answer is yes. Otherwise, it would not continue to be one of the highest-selling categories of seafood. Tuna is enjoyed by anyone with a palate. The different types of tuna fish are especially good when blended and mixed with other foods and condiments.
It must be said, however, that the widespread use and ubiquity of tuna partly account for its success as a food product. So many people have grown up eating tuna products of various kinds that it has become a virtual staple of the modern diet.
Is tuna nutritious?
Canned tuna contains essential nutrients such as Omega-3 fatty acids, protein, selenium, and Vitamin D. The nutritional level of canned tuna is determined by the oil or water that is packed in with it. Omega-3 is good for the heart and the functioning of the brain.
It is also good for bodily growth and development. Albacore and bluefin have the highest levels of Omega-3.
Tuna and the Environment
Concern about the ecological impact of human activity has increased significantly over the last two decades. Nearly every industry is scrambling to reduce the harm that its operations inflict on the environment. This reassessment is not limited to companies that burn carbon or produce non-biodegradable waste.
The fisheries industry has also come under the gun. The issue of overfishing has been put front and center in recent debates over sustainability.
1. The International Context
The United States is a member of the Inter-American Tropical Tuna Commission, the Western and Central Pacific Fisheries Commission, and the International Commission for the Conservation of Atlantic Tunas. As tuna fish are a highly migratory species, nations must cooperate if the species is not to be fished to extinction or completely wiped out in certain regions. The above-mentioned organizations were designed to facilitate such cooperative management.
The biggest problem is that the demand for tuna continues to grow. As once underdeveloped economies grow wealthier and the purchasing power of their populations increases, their appetite for tuna expands. More than seven million tons of tuna fish are captured each year. Over a third of the tuna species harvested are done so at biologically unsustainable levels.
International organizations have stepped up to deal with this problem. Foremost among them is the United Nations. The United Nations Environment Programme (UNEP) has invested fifty million dollars in a program known as Global Sustainable Fisheries Management and Biodiversity in Areas Beyond National Jurisdiction (ABNJ).
This is a very long-winded name for an organization, which may give it an air of pretension and wastefulness to some. But the ABNJ has gotten results. It has made progress in protecting the biodiversity of international waters and has minimized the impact on local ecosystems. Its success is in the figures. Between 2014 and 2019, the number of tuna stocks suffering from overfishing went down from thirteen to five. Marine pollution has also gone down.
2. The Local Context
Whenever the issue of fishing in the name of food security, economic development, and employment comes up, various developing countries are usually invoked. While it is true that over eighty states have tuna fisheries, and that hundreds of thousands of people rely on the industry for their livelihoods, the peoples and countries that rely on tuna fishing are not all in the third world.
The tuna industry also touches towns and people in Scotland, America, Japan, and other rich countries. The fishermen and tuna companies in these countries have built up powerful political blocs that push for rules, regulations, and legislation that will protect their economic interests.
On too many occasions, illegal fishing is blamed on operators from the developing world. However, there are plenty of tuna trawlers from the developed world that also engage in illegal, unreported, and unregulated fishing. Tuna stocks in the North Atlantic and Pacific are as threatened as those in the Indian Ocean and South Pacific.
Should I Eat Tuna?
The previous section would seem to discourage any environmentally conscious person from buying or consuming tuna. But do not make such a decision before you have gotten the complete story!
Yes, you should buy tuna. You would be depriving yourself of too many wonderful tastes and gourmet experiences if you gave up on tuna fish. The various kinds of sushi tuna are especially delightful. Tuna fish dishes that are prepared with care and imagination make for some of the best food that you will find anywhere.
If you are compulsively social and like having people over to your home for dinner, tuna can give you many more options for starters and main courses. You don’t want to limit yourself—to the detriment of your hospitality—by giving up tuna fish. Bluefin, yellowfin, albacore, and bigeye tuna dishes can please. You can also make tuna salad or various starters made from canned tuna.
But what about the sustainability issue?
This problem has largely been solved. I said before that the tuna fishing industry has come under the gun. Part of this environmental riflery has been the effort of non-profit organizations to certify certain tuna brands as sustainable. The Marine Stewardship Council is the foremost organization involved in this activity.
You should look for the MSC seal of approval if you want to buy tuna that meets the criteria for sustainable fishing.
You should also look closely at canned tuna labels, and choose “pole-caught”, “troll-caught”, or “pole and line caught”. Here, the issue of bycatch comes into play. Bycatch is the incidental catching of unintended species—that is, threatened or endangered species such as sea turtles, sharks, and seabirds.
Tuna that has any one of the three labels just mentioned will have been caught with no bycatch.
It is wise to avoid any tuna that is without certification or labeling of any kind. If the methods of the fishery cannot be confirmed, then you should pass on the brand. Certified cans of tuna are the only ones that come from industry sources that are constantly monitored and inspected.