Commercial fishing boats
have negatively impacted wild fisheries with nets that don’t discriminate
between size class and the reproductive maturity of fish species. Most boats
are equipped with technology that target a school of fish, with one catch
potentially wiping out the next generation, leaving some populations depleted
or completely destroyed. Recovery takes a while, and the disappearance of key
stone species over time affects the collective ecology and abundance of marine
animals and plants. Each year approximately 640,000 tonnes of fishing gear and
nets are discarded by the fishing industry. Is it game, set and match in the
world’s oceans?
Conservation of the Reef along the east coast of Australia with the Great Barrier Reef Marine Park has made a huge difference
to the abundance of tropical reef fish and other marine life. ‘No take’ and
‘take’ zones guide recreational and commercial fishers to places where fish and
crabs etc., can be legally caught.
The ‘no take’ zones allow
animals to breed without fishing pressures, which in turn increases the numbers
of wild fish available in ‘take zones’. Marine Parks around Australia’s
coastline and worldwide, continue to positively affect marine life abundance
and diversity, supported by community awareness campaigns.
More people are investing
their expertise and knowledge into aquaculture as a sustainable alternative to
the wild caught fisheries. There are a range of methods used to breed fish,
crustaceans, shellfish and algae for restaurants and the markets, in fresh
water or saltwater aquaria/ponds. Similar to any competition, aquaculture has encountered
its fair share of criticism; but improved technologies have made it more
commercially viable.
Nets abandoned by fishing
crews, continue to make a big haul at sea though, fatally trapping whales,
dugongs, fish, crocodiles, sea birds, sharks, seals and dolphins, as they drift
along the oceans currents. Recently, a spate of shark attacks along beaches
prompted the introduction of drum lines in New South Wales to curb the risk to
surfers and swimmers. Drones equipped with cameras are currently being trialled
to alert authorities if shark activity is observed along beaches. This method
combined with drum lines is considerably less threatening to marine species,
compared to the use of nets.
Turtles and seabirds
recurrently swallow or are entangled by fishing line, tackle, plastic debris
and nets, despite efforts led by community groups like Clean Up Australia to
remove marine debris and rubbish in general. One of the hotspots for discarded
fishing nets is the Gulf of Carpentaria in Australia’s north. Seven species of
marine turtle are listed as threatened, including the Hawksbill, Green, Olive
Ridley, and Flatback turtles. Ghost nets are the common cause of death.
Ghost nets are a
serious environmental hazard, not just to animals, but also to anyone going out
on a boat. A net can jam an engine. If you spot an injured animal, please
contact a wildlife rescue association or a veterinary clinic for assistance; and safely
throw discarded nets or tackle into a bin. It’s just one thing to do, but if we
all do it, this deadly game out at sea might be over for good.
Written by Gabrielle
Ahern
Salty Wave Blue
– Into all things ecology.
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@SaltyWaveBlue on @Instagram and @Twitter
If you would like to
see images of animals like turtles, rays, whales and seals in their marine
environment, please take a look at my Pinterest site: https://www.pinterest.com/saltywave
