PORBEAGLE SHARK
PHYSICAL DESCRIPTION
Their body is spindle shape and, rather heavy.
Their head is stout, and
snout is pointed. The mouth is moderate to
large, the teeth are similar in
upper and lower jaws with large central cups and
two lateral cups. There
are 24-32 tooth rows in the upper jaw, 20-26
tooth rows in the lower jaw.
The eyes are large with large gill slits. It has
two dorsal fins, first is larger
than the second. The colour is dark bluish gray
to bluish black above, white
tip on the lower trailing edge of the first
dorsal fin, lower surfaces are dark
on outer half, mottled white and black toward
the base, belly is white, unblotched.
COMMON NAMES
Porbeagle, Mackerel shark.
SWIMMING PATTERNS
Porbeagle sharks swim with a series of muscle
contractions along with
sideways movement of the tail.
BREEDING AND FEEDING HABITS
The pups are developed inside the mother, with 1
to 5 pups per mother.
They are born alive, 60-75cm long, usually in
the summer in northwest
Atlantic waters although females with young may
be found throughout the
year.
Feeding: The porbeagle is said to feed
mainly on small pelagic schooling
species such are herring, gaspereau, and
mackerel, although cod, white
hake, red hake, haddock cusk and squid are also eaten.
HABITAT
They are usually more common on the continental
shelves but occur
sometimes well offshore, but they are also known
to be in inshore areas,
including harbours. They are commonly in
Canadian regions during
the spring, summer and fall, but are
occasionally caught on fishing
banks during the winter months. They seem to
prefer cool rather than cold
waters, and are usually found in temperatures
below 16 degrees Celsius.
GROWTH
There is little information on the rate of
growth. They are thought to reach
sexual maturity at about 5 years of age or older
and have a life expectancy
of about 20-30 years. Age determination are
considered possible by
counting the growth rings on the vertebral centra.