Horn Shark | The horn shark is a small species of shark,
natively found in the coastal waters of north-west North America. The
horn shark is named for the broad, flattened head and high ridge found
behind this shark's large eyes that is almost horn-like in appearance and makes this shark one of the hardiest of all shark species. The horn shark is endemic to
the Pacific north-east, and is only found in the warmer waters off the
coast of California. The horn shark is most commonly found along the
temperate to sub-tropical continental shelves where it spends most of
it's time in search of hard-shelled marine organisms to eat off the sea-bed.
The horn shark is a small
species of shark that typically measures about 1 meter in length. The
horn shark can be most easily recognized by a short, blunt head with
ridges over its eyes and two high dorsal fins with large venomous spines.
The horn shark is usually a brown or grey colour with many small dark
spots across it's body. The horn shark is a clumsy swimmer that prefers
to use its flexible, muscular pectoral fins to push itself along
the bottom of the ocean rather than swimming through it. The horn shark
is usually solitary, though small groups have been recorded
(particularly during the mating season). During the day, horn sharks
rest motionless, hidden inside caves or crevices, or within thick mats
of algae, though they remain relatively alert and will swim away quickly
if disturbed. After dusk, they roam actively above the reef in search
of food.
Horn sharks are carnivorous predators and although they do eat fish and marine invertebrates
on the ocean floor, around 95% of the horn shark's diet is made up of
hard-shelled molluscs and crustaceans which they horn shark uses its
short, hardened head to break them apart before eating the fleshy insides. Horn sharks also feed on echinoderms such as sea urchins and star fish.
Despite being quite complex predators themselves, the relatively small
size of the horn shark means that they are by no means at the top of the
food chain within their natural environment. Large species of fish prey on the horn shark along with other sharks that share their native range. Humans are also one of the horn shark biggest
threat as although they are not really hunted, horn sharks are often
caught as by-catch when we are fishing for other things.
Horn sharks tend to mate in
between December and January with the female laying her eggs 4 to 5
months later. Female horn sharks can lay up to 24 eggs over a
period of 2 weeks, which float in the ocean in a spiralled casing. The
female horn shark is one of the only shark species to display pre-natal
care, as she collects her eggs in her mouth before depositing them into
the safety of crevices in the rocks. The horn shark pups usually hatch
within a month.
Today, as so little is known about the horn shark population off the Californian coast, they have been listed as being Data Deficient
as their is not enough information about their status in the wild. Like
many other species however, the horn shark populations are being threatened both by water pollution and commercial fishing in the area.
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