Page 11 - My FlipBook

THE sCIENCE BEHIND THE STORY

The proof is in the pictures.
Armed with high-speed video cameras,
biologist Alexander Wilson and his colleagues
got into the water with Atlantic sailfish off the
coast of Mexico. While snorkeling alongside
these big predators, the scientists filmed them
in action.
Sailfish work together to hunt small fish
such as sardines. “It is an amazing experience,
actually,” Wilson said. “What first appears
random or chaotic is actually quite an orderly
process, where groups of sailfish will cut off a
school of sardines near the seafloor, then push
them towards the surface where they can be
controlled as a type of bait ball.”
Once the sailfish have corralled the sardines,
they take turns attacking. The scientists
replayed their videos in slow motion to reveal
Researchers come face to face with hunting
the details of these attacks. Typically, a sailfish
sailfish as they film these highly skilled
swims up and slowly inserts its bill into the predators attacking their prey.
bait ball. Then it whips its bill from side to side
like a sword, slashing at a speed of about 20
feet (6 m) per second. That’s roughly the speed
at which the tip of a baseball bat moves when a sailfish swoops in and swallows it whole.
baseball player swings hard at a pitch. “The turn-taking ensures that all the sailfish
Each slashing attack injures more sardines, get some food and don’t injure each other by
making them easier to catch. A sailfish uses making a mad dash at the sardines at once,”
its bill to do this too. It taps an injured sardine Wilson said. The sailfish keep slashing and
with the bill’s tip, just hard enough to make the tapping—and eating—until the last little fish
little fish swim out of the bait ball. Then the is gone.

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