Credit: Illustration by Diane Rome Peebles
Family Lamnidae
Description & Behavior
The shortfin mako shark,
Isurus oxyrinchus (Rafinesque, 1810), aka mako, shortfin, short-finned
mako, blue pointer, mackerel shark, blue dynamite, bonito, spriglio, paloma—is a
truly beautiful animal. It is a well-adapted and active pelagic shark. Like its
cousin, the great white, it
keeps its body temperature warmer than the surrounding water temperature using a
high metabolic rate and heat-exchange system. It has a remarkable swim speed
reaching sustained speeds of 35 kph
(with bursts over 80 kph) and has been known to travel over 2,092 km
in little over a month. These sharks have a rapid growth rate, twice as fast as
some of the other Lamnidae species.
Males mature at around 2 m while females mature at about 2.6 m. A
maximum length of 4 m long and max weight over 505.8 kg
has been recorded.
There are two types of mako, the most common and
widely spread is the shortfin mako, Isurus oxyrinchus, and the less
common and more specialized longfin mako (or big-eye mako), Isurus
paucus. Makos represent the largest, fastest most sophisticated species of
pelagic shark on the planet.
An ancient relative Isurus hastilus
is nearly identical in terms of tooth structure and function. The ancient
mako hastilus was probably 6 m long and
nearly 2,800 kg; it was the Cretaceous grand mako that shared the
seas with kronosaurs, ichthyosaurs,
and plesiosaurs.
The mako sharks
are an easily recognizable shark exhibiting all the traits of a Lamnid, they are an
extremely robust and streamlined pelagic shark with well developed eyes (larger
in the longfin) and an endothermic circulatory system (warm bloodedness) that is
known to maintain elevated muscle temperatures of up to .6°C above
the ambient water temperature. Makos are heavily built with the trademark strong
caudal keels that are a common feature among Lamnids such as great whites, porbeagles and salmon sharks.
Longfin makos are
apparently a more deep water tropics-dwelling predator of which little is known.
It wasn't even described as a separate species until 1966.
Makos have
striking coloring with deep purple to indigo dorsal surfaces, silvery sides, and
white ventral surfaces. The longfin mako has a shaded coloration around the
mouth and underside of the snout, unlike the shortfin mako which is snow white
around the mouth and under-snout. Only the blue shark can rival the makos
for beautiful coloration.
Mako sharks have five large gill slits,
well-developed eyes (slightly larger in the longfin) and pronounced knife-like,
non-serrated teeth. An extremely fast and active shark, it was propelled to
"big-game fishing" fame by author Zane Gray who was taken by the animals
menacing appearance and volatility during the early part of this century.
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