AD 2016 Q2

This image is a digital
composite of several photos
taken of a fin whale in
the Pelagos Sanctuary
for Mediterranean Marine
Mammals. Stringy white
copepod parasites can be seen
attached to the whale.
[
BY DOUG PERRINE
DOUG PERRINE
[
throughout the day. Fin whales in the Ligurian Sea (the
area of the Mediterranean south of Italy’s Liguria region
and north of the island of Corsica) feed mostly at night
and at depth. Around Lampedusa, the whales were also
feeding in groups, possibly collaborating to herd prey
— a behavior not previously recorded in Mediterranean
fin whales. The question that most bedeviled Tethys
founder Giuseppe Notarbartolo di Sciara was if these
whales belonged to a separate southern Mediterranean
population or if they were the same whales his
organization was studying during the summer in the
Ligurian Sea near the border of France and Italy.
The fin whale is one of the most mysterious and
elusive large animals on the planet and is in many
ways an oddity of the animal kingdom. In nearly all
vertebrates the left side of the body is a mirror image of
the right. Fin whales are an exception. The lower jaw on
the left side is a typical whale gray, while on the right it’s
a brilliant white. The right dorsal surface has swirling
patterns known as “blaze and chevron” that are unique
to each individual and allow the Tethys researchers to
photoidentify each whale. Scientists speculate that the
reflectivity of the white lower jaw may be used to startle
and herd prey, but any functional advantage of the blaze
and chevron is harder to conjecture.
Fin whales push the extremes of the animal kingdom
in speed, size and feeding ecology. They are one of
the largest creatures on the planet and one of the
fastest swimmers in the ocean. Calculations predict
a theoretical maximum speed of around 30 miles per
hour, and Pierantonio believes he has seen one swim
at least that fast. (Faster estimated speeds by marlin,
sailfish and dolphins are based on the animals jumping
above water or riding in boat wakes.) Fin whales,
which are thought to plunge to nearly 2,000 feet in
the Mediterranean in search of krill, may also have the
deepest feeding dives of any baleen whale.
Fin whales do not simply swim along with their mouths
agape to filter plankton (as right whales do); instead
they capture their prey of krill or small fish by lunging
repeatedly at high speed, engulfing volumes of water
that may actually be larger than the size of the whale’s
body before it opened its mouth. Each lunge requires
rapid acceleration and an enormous expenditure of
energy. Researchers at the University of British Columbia
described this process as “one of the most extreme
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