Bluefin tuna are (partially) warm-blooded! Most fish stay the same temperature as the water, but bluefin have special blood vessels that trap heat from their muscles. This keeps them up to 18°F warmer than the ocean around them, helping them hunt and even see better in cold water! 🌡️

Bluefin tuna are deep-sea divers! They can dive nearly 3,000 meters to chase squid and fish. Their bodies are built to handle freezing water and high pressure. 🤿

Some tuna can never stop swimming! While many fish can pump water over their gills to breathe, albacore must keep moving to get oxygen. Even when they “rest,” they’re still gliding forward. 🐟

A school of tuna can be wider than a city! Tuna often travel in huge groups, sometimes up to thousands of tuna. Some schools have stretched up to 19 miles across! 🚌

They are crossed oceans! Some species migrate thousands of miles, and bluefin have been tracked swimming from North America all the way to Europe. Because they control their body temperature, they can survive in tropical and near-arctic waters. 🌎

Tuna flesh is dark red because of myoglobin. Myoglobin is the same protein that makes beef red. It helps their muscles hold oxygen, giving them the energy to swim nonstop. 🩸

Tuna can swim faster than some speedboats! Their bodies are shaped like race cars. They’re one of the most efficient shapes in nature, with crescent tails and tiny fins that cut drag. Albacore can reach speeds over 50 mph! 💨

They can weigh as much as a small car! The biggest Atlantic bluefin can grow 13 feet long and weigh more than 2,000 pounds! 🚗

“Tuna” actually refers to 15 different species of fish! It includes bluefin, skipjack (the kind most canned tuna comes from), yellowfin (Ahi), albacore, and many others. 🐠

A single tuna can cost as much as a luxury home! Bluefin are among the priciest seafoods, and some have sold for over $3 million at Japanese auctions. 💰