Basking Shark
The
basking shark (Cetorhinus maximus) is the second largest fish
in the world, second only to another filter feeder, the whale
shark. This animal can attain lengths of at least 10 meters
(33 feet), but the average size is 7-9 meters. They can weigh
up to 4 tons. The shape of its snout is conical and the gill
slits extend around the top and bottom of its head. Associated
with the gills are structures called gill rakers. These gill
rakers are dark and bristle like and are used to catch plankton
as water filters through the mouth and over the gills. The
basking shark is usually grayish-brown in colour and often
seems to have a mottled appearance. The caudal (tail) fin
has a strong lateral keel and a crescent shape. The teeth
in the basking shark are very small and numerous and often
number one hundred per row. The teeth themselves have a single
conical cusp, are curved backwards and are the same on both
the upper and lower jaws.
Basking sharks are a migrating species and are believed to
overwinter in deep waters. They may occur in either small
schools or alone. Small schools in the Bay of Fundy have been
seen swimming nose to tail in circles in what may be a form
of mating behavior. Basking sharks are not aggressive and
generally harmless to people. The number of basking sharks
is unknown, but may be decreasing since the basking shark
is hunted for its meat, fins and oil.
Basking sharks are slow swimmers, going no more than 3 mph
(5 kph). They swim by moving their entire bodies from side
to side (not just their tails, like some other sharks do).
The basking shark is a pelagic animal, occurring in warm
coastal and cool temperate waters, but often straying inshore.
It is commonly seen very near the surface of the water along
the coast of Nova Scotia and New Brunswick. During the winter
these animals migrate to deep water. Some may overwinter in
the deeper waters of the Gulf of St. Lawrence. They spend
most of their time at the surface, hence their nickname the
"sun fish."
The basking shark ranges throughout the north and south Atlantic
Ocean, the Mediterranean Sea, north and south Pacific Ocean,
the Sea of Japan, off southern Australia and around New Zealand.
In Canadian waters the basking shark is often seen during
the summer and fall (May to September) near and around the
coastline. It ranges from White Bay and Notre Dame Bay Newfoundland,
to the Gulf of St. Lawrence, on the Scotian Shelf, along the
Nova Scotia coastline, in the Bay of Fundy and south towards
the U.S. border.
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