Who
Are You, Anyway?
Identifying
Individual Manatees
Have you wondered how scientists like Ranger Wayne and Cathy Beck identify
one manatee from another in the field? It’s a fascinating process
that all started with sketching a manatee's individual visible features,
and now has gone to the level of a state of the art computerized photo
database with more than a thousand manatees in it. In the end, though,
it all comes back to what you can see.
Spinning
Knife Blades
Fortunately
for the scientists, each manatee has unique physical features that distinguish
it from other manatees. Unfortunately for the manatees, most of their
unique features are actually scars and injuries the manatees received
in collisions with powerboats. The propeller of a boat is like a spinning
knife blade under water.
Credit:
USGS,Brd,Sirenia
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If
the manatee survives the boat strike, it is left with unique scars,
which scientists use for identification. |
When it strikes
a manatee, the manatee is cut by the propeller blades, and may even lose
a part of its body, like part of its tail. A boat motor can also cut a
Manatee with a "skeg", which is like a vertical metal fin at
the bottom of the motor.
Sketching
the Scars
Manatee scientists photograph or sketch the scars and features of individual
manatees so that they can be identified and studied. The most extensive
identification system of this kind is the database maintained by Sirenia
Project biologist Cathy Beck. Known as the manatee Individual Photo-identification
System (MIPS), it is a computerized photographic catalog that currently
includes over 1,400 wild Manatees.
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Underwater
sketching |
On a different
scale, Ranger Wayne takes photographs and maintains a Blue Spring "Scar
Sheet", which shows drawings of the identifying scars and features
for the manatees at Blue Spring. (You'll get the chance to use some of
Ranger Wayne's scar sheets.)
And on an
even smaller scale, if a scientist spots an unidentified new manatee,
she will sketch a drawing of the scars right there on the spot--even underwater!
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