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Hi everyone and welcome to the whale shark bonus reel where I get to share some of the
extra material I learned while researching whale sharks that just didn't quite fit in
the documentary video.
For instance, you may be surprised to learn that whale sharks were not discovered and
officially described until 1828.
How did scientists miss seeing the biggest fish in the ocean?
Well, whale sharks are pelagic, which means they live in the open ocean, and because they
are fish, not air breathing animals like whales or sea turtles, they do not have to come to
the surface to breathe, making it much less likely for them to be spotted by sailors.
Even in more modern times, famous ocean explorer Jacques Cousteau only saw two whale sharks
in the decades that he was exploring the ocean.
Two!
You've seen more whale sharks in the time I've been talking than Jacques Cousteau saw
in his entire life.
That is made possible because some time in the 1990s, someone told the scientists that
whale sharks like to gather in coastal areas to feed, often in groups of dozens or even
hundreds of sharks, and they return to the same area year after year.
Apparently fishermen had known about it for generations, but no one thought to tell the
scientists who came out year after year to study sharks.
Once scientists became aware of these huge, predictable gatherings of whale sharks, it
became much easier to study them.
They were able to tag and photograph thousands of sharks, tracking them as they traveled
around the ocean.
This is how we learned that whale sharks sometimes dive deep down and regularly swim thousands
of miles, often back and forth across oceans to different feeding grounds.
As it turns out, the pattern of spots that a whale shark has on its back is unique.
Every whale shark is different! and this allows scientists to identify individual whale sharks
when they reappear in a different place or a different time.
Unfortunately, trying to match up spot patterns is difficult and time-consuming, so scientists
took an algorithm from NASA originally intended to match star fields for the Hubble Space
Telescope and adjusted it to help match whale shark spot patterns so individuals can be
identified.
There's still a lot of research to do about whale sharks.
No one knows where whale sharks mate or give birth, and only one pregnant whale shark,
caught back in 1995, has ever been examined by scientists.
Advances in tracking whale sharks are allowing scientists to find more places they gather
and add more pieces to the puzzle.
Okay, one more fun fact about whale sharks: the reason they don't eat humans or large fish
is because their throats are only the size of a quarter, or about 2.4 centimeters across
for you viewers outside of the United States.
We just wouldn't fit!
I hope you enjoyed the whale shark bonus reel today, and I'll see you next time.
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