Fish: How your choices affect the ocean

The oceans are in bad shape.

It’s hard to imagine that something as big as the ocean can run out of fish, though scientists have estimated that by 2050, this will be the case. In fact, population counts show that we have already consumed 90% of the ocean’s big fish; important apex predators such as sharks and tuna, wildly unbalancing the marine ecosystem.

The main problem with fishing is the methods used to catch the fish, such as large nets that damage the ocean floor and sustain large levels of bycatch (creatures such as turtles, sharks and dolphins unintentionally caught in the nets).

The intuitive response might be to eat only farmed fish, although this solution is problematic. Farmed fish are fed with fishmeal. Ironically, to create 1kg of farmed fish, 5kg of smaller fish must be fished out of the ocean, effectively making farmed fish 5 times worse than wild fish.

So what do we do, stop eating fish altogether? Doesn’t that seem like an impossible goal?

There is nothing inherently wrong with eating seafood; humans have eaten fish for as long as they’ve known they could. The problem is that when technology improved beyond pole and line fishing, we started to secede the ocean’s ability to replenish.

So quite simply, the answer is to only eat species of fish that maintain healthy stocks, and that are caught using sustainable methods, decreasing bycatch and environmental damage.

Helping us learn which fish are and are not sustainable to eat, Greenpeace and the Australian Marine Conservation Society have collaborated on the iPhone app “The Sustainable Seafood Guide”.


The guide is sorted into “Better Choice”, “Think Twice” and “Say No”; easy to understand categories, with well-explained rationale.

Apps like this make it easier and easier for people to make informed decisions. As everyone is starting to understand the difference between “cage” and “free-range” eggs, hopefully we can begin to make smarter choices through the purchase of only sustainable and environmentally friendly seafood.

At the end of the day, the most powerful message we can send is as consumers. By abiding by these guidelines, we can make sure we are not supporting wasteful, unethical and unsustainable fisheries.

Download the app for your iPhone here – Sustainable Seafood Guide [iTunes]

Or view the guide online for seafood here – and Australian canned tuna here –

You can find out more about overfishing and marine conservation at

About the writer: John de Jong is a Dive Control Specialist who has worked in the SCUBA industry throughout South East Asia. When he’s on land, he writes about history, politics and culture for various publications. You can check out his work at

Fish image sourced from