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Superfish: Bluefin Tuna Facts

Superfish: Bluefin Tuna

Superfish: Bluefin Tuna (View larger version)

  • Bluefin have many senses of direction. They can use their pineal window to follow the sun and celestial cues. They make use of their visual, olfactory and electromagnetic senses to stay on courses or follow prey. Furthermore, they are thermotactic, polarotactic, and rheotropic.

  • Bluefin, when fighting fishermen, can have such high bursts of muscle activity that they cook their own flesh.

  • Bluefin may travel migration routes of up to 10,000 miles, and have been documented travelling 6,200 miles in fifty days.

  • They appear to have social interactions, as shown through milling and swimming in geometric patterns.

  • A giant female bluefin may release 40,000,000 eggs in a year (128.5 eggs/g); yet, after 10 years, on average less than one offspring remains when fishing pressure is great.

  • Bluefin can be up to 10 feet long and 1,000+ pounds and reach speeds of nearly 50mph.

  • Giant bluefin are warm-blooded, able to tolerate temperatures to 45 F with incredibly efficient (98%) heat exchange in their countercurrent cardiovascular system (68).

  • The giants can grow at 7.5 percent per month through the summer, theoretically going from 450 to 600 pounds from June to October.

  • Despite now being nearly fished to extinction, bluefin were once thought to be poisonous and were rarely consumed prior to the 20th Century.

  • Capable of beating their tailfins some 30 times per second, the tail of a swift bluefin appears only as a blur to the human eye.