Tuna

The Tuna (マグロ, Mageru) is a rare fish that can be found in the Ocean at any times of the day between the months of November and March. The fish sells for an expensive 7,000 Bells at Tom Nook's store. In the "Bugs and Fish" window in City Folk, it says, "Since sushi has become popular everywhere, all cuts of this fish are expensive." The fish has a huge shadow size and does not belong to any families or groups.

In City Folk
Upon donating to the Museum, it can be found in the back tank with other ocean fish. When given the fish, Blathers will say this: "If tuna stop swimming, they actually lose the ability to breathe and can perish! ...Which means that even while resting, this fish just keeps swimming, eh wot? I really prefer to focus on resting up rather than napping... Rather lucky I was born an owl, wot wot!"

In Wild World
Blathers will say this when donated to the Museum: "If a tuna stops swimming, it will stop breathing and expire, eh wot? As you can imagine, this means that it must swim when it sleeps as well. I think every day about how marvelous life would be if I could work in my sleep!" One can find the tuna in the back tank with the other ocean fish.

In New Leaf
The information board in front of the tank that holds the tuna says the following:
 * Tuna can reach almost 10 feet in length and weigh over 800 pounds, which is huge in the fish world. Combining this great size with their good flavor makes them literally the biggest catch for most anglers. Tuna can't breathe when they aren't moving, so their entire lives revolve around constantly swimming. To sleep, they merely slow down. This ability to swim while sleeping is a huge advantage. They're also rather fast, capable of beating both sets of fins so hard they reach speeds of 50 mph."

Encyclopedia Information
Once the player has caught a fish or bug, they can find information about it in the fish and bug menus.

Further Information
There are various types of tuna in existence. The type of tuna that appears in appears to be a Northern bluefin tuna, judging by the overall shape and coloration of the body. As a result of its uses, it has become overfished and due to its late maturity, it is increasingly difficult for it to reproduce to sustain the demand. It preys on Squid, crustaceans, Horse Mackerel, sardines, and herring.