Fishing trawlers are one of the
reasons why all types of marine
turtle are now in danger of
becoming
extinct
. Although
it is forbidden to hunt marine
turtles in many areas, turtles
are still accidentally caught
in the nets of fishing trawlers.
Turtles are reptiles, which
means they have to come to
the surface to breathe in air.
The nets stop them doing
that and they drown.
ON THE EDGE
A sea turtle in the Red
Sea comes to a coral reef
to feed. Red Sea haddock
are threatened by fishing
boats and nets, which
also damage the coral
reefs.
Top predators
Tuna and sharks are important
predators, but up to 100 million
sharks are caught worldwide every
year, mainly for their fins and as
by-catch. Removing a top predator
can have a devastating effect. For
example, sharks prey on rays, which
feed on
scallops
. When the number
of sharks off the East Coast of the
United States dropped steeply
after the 1970s, the number of
rays increased. This led to the
collapse of scallop fishing.
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