Sharks are
unfortunately disappearing at an alarmingly fast rate due to several threats. In
a study conducted by Oceana, researchers estimated that as many as 100 million
sharks are still caught and killed worldwide due to bycatch, illegal fishing,
and the demand for shark fins. This makes it extremely difficult for endangered
sharks to survive.
BYCATCH
Bycatch
is the accidental capture of non-target fish and other marine life, and occurs
in fisheries around the world. When lines are unattended, such as in some longline
fisheries, the toll can be particularly high. The species that are most at risk
include dusky sharks and scalloped hammerheads. Dusky shark populations off the
Atlantic coast has declined by 85 percent. Scalloped hammerheads are extremely
susceptible to fishing mortality due to their uniquely shaped and sensitive
bodies.
ILLEGAL FISHING
Oceana
reports that up to 24 countries may be catching sharks within the Atlantic and
Mediterranean Sea without reporting such catches. Commercially-caught species
like mako and blue sharks are fished without any restrictions.
SHARK FIN DEMAND
The
international fin trade is one of the greatest threats to shark species. It is a
wasteful and harmful practice in which only two to five percent of the shark is
even used — once a shark's fins are cut off at sea, the shark is tossed back
into the water to drown.
RECREATIONAL FISHING
The impact
of commercial fishing on shark populations is astonishing. Recreational fishing
for sharks is popular in many places and species targeted are blue sharks,
shortfin mako, porbeagle, and thresher sharks.
HABITAT LOSS,
POLLUTION AND ENVIRONMENTAL DEGRADATION
Coastal
development has increased significantly which has altered habitats, increased
levels of pollution and resulted in the general environmental degradation. Many
shark species use inshore coastal and estuarine habitats as a safe place for
finding food, giving birth and growing up away from predators and competitors. Thus,
they are vulnerable to negative changes in their habitat.
Sharks
are susceptible to pollution (filtered from land activities or directly
deposited into the seas) and environmental contamination. As apex predators
with very slow growth, they accumulate the pollutants and toxins in the
environment and bioaccumulating all the toxins of their prey.
REFERENCES
http://www.defenders.org/sharks/threatshttp://shark-facts.com/http://oceana.org/blog/what-are-some-biggest-threats-facing-sharks
http://www.sharksavers.org/en/education/sharks-are-in-trouble/other-threats-facing-sharks/
