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Why Overfishing Persists

Studies predict our oceans could be fishless by 2048. An apocalyptic vision, because with empty seas, humanity really does not stand a chance.


Oceans are the lifeblood to our planet, connected to us through every breath we take, every drop of water we drink, whilst housing the largest ecosystem on Earth. For too long, mankind has taken the ocean for granted and now the seas are under threat. Positioned on the cusp of a series of cataclysmic tipping points, those of ‘no return’. The culprits: copious, with overfishing taking up an exceptionally large stake.


The fishing industry is relentless. Massacring billions of lives a year, scratching the seabed raw and choking marine mammals senseless, the industry has become beyond unsustainable, jeopardizing the World Ocean ecosystem. With fewer fish in the ocean, catch per Unit Effort (CPUE) has increased, meaning fishing fleets spend more time on the sea, exhausting more fuel and resources, only to catch fewer fish in a set period of time. For example, CPUE has doubled since 1950, despite the area being fished increasing 60% and fishing effort increasing by a factor of 10. With no time to recover from these shocks, fish stocks are ever decreasing, with 64% of formally unassessed fish stocks estimated to be overexploited. Yet, the fishing industry persists.

The solution in basic terms, is to ensure fleets do not exceed the Maximum Sustainable Yield (MSY) of fish stocks. MSY indicates the total allowance catch (TAC), meaning the maximum amount of fish fishermen from a particular country and vessel can take from the ocean in order to maintain the fishery. However, uncertainty relating to confounding factors, means TAC estimates are presented as a range with less confidence attached to higher quantities. Regulators routinely taking higher TAC estimates, compounded by intense lobbying from the fishing industry, means quotas are set above MSY advice, depleting stocks. The state should create laws to discourage this, for example the USA Magnuson–Stevens Fishery Conservation and Management Act (2012), makes it illegal for TACs to be set higher than scientific advice. However, in Europe, the role of states fall short. For example, from 2001-2015, the EU Common Fishery Policy consistently set TACs 20% above scientific advice, overexploiting 70% of EU stocks.

However, even in scenarios when scientific advice is heeded, TAC estimates are exceeded at sea for two main reasons. Firstly, due to ‘top-grading’ as fish already caught and dead to be thrown over sea, as fisherman wait for bigger fish to reel in higher profits, throwing the smaller ones overboard. Secondly, due to illegal landings, whereby fishermen go to extortionate lengths to fish beyond their quota, economically motivated to sell more for profit.

A third reason for overfishing is due to ecological factors, unforeseen in scientific models, which may rapidly decrease fish populations. Such as if their food supply rapidly diminishes, a disease breaks out, or rising sea temperatures from climate change for example. To remedy this, TAC estimates should be abided, with a greater buffer zone to account for the natural rise and fall of species within complex ecosystems, in addition to people eating less fish.



Written by Stephanie Frank


Stephanie Frank is a columnist at DecipherGrey.