Scombridae

Atlantic bluefin tuna

Thunnus thynnus

Warm blood crossing the whole Atlantic

• Blue
• Silver
• Tropical
• Globally widespread
• Marine fish
• Fusiform
• Large
• Tropical fish

Built on a titanic scale for relentless transoceanic cruising, the Atlantic bluefin tuna stands as one of the fastest and most formidable predators roaming the North Atlantic Ocean. Its metallic, midnight-blue back transitions smoothly into iridescent silvery-grey sides adorned with faint, shifting bars, tapering into an exceptionally rigid caudal keel and crescent tail. Internally, a specialized countercurrent vascular network known as the rete mirabile enables regional endothermy, keeping core muscles, brain, and eyes significantly warmer than the surrounding frigid marine waters. Ranging from subpolar feeding grounds off Norway and Canada south to subtropical breeding basins in the Mediterranean Sea and Gulf of Mexico, it navigates waters from surface churn down to one thousand meters depth. Propelled by powerful thunniform locomotion reaching speeds near seventy kilometres per hour, schools hunt relentlessly for herring, mackerel, capelin, and squid. Capable of surviving over thirty-five years, these ocean giants reach maximum recorded total lengths up to four hundred and fifty-eight centimetres and body masses exceeding six hundred and eighty kilograms.

Sources: NOAA Fisheries — Atlantic Bluefin Tuna