Environmental own goals: Overfishing

Underneath the vast veneer of our planet's oceans there is a titanic struggle for survival going on.

It's a race against time and a result of advances in fishing technology, perverse subsidies, illegal and destructive fishing vessels and the plain lack of common sense. What we are witnessing and what we are allowing to happen is the transformation of our Blue Planet into a wet desert.

Take a look at these facts: the global fishing fleet is 2.5 times larger than what the oceans can sustainably support. Already, 52% of the world's fisheries are fully exploited and 24% are overexploited, depleted or recovering from collapse.

In a single human lifetime we have inflicted a crisis on the oceans greater than anything we've ever done to the rainforests.

And the coup-de-grace of it all is that we are getting less food from the sea. We're landing smaller, younger fish. We're wiping out entire fish populations.

And so our industrialized fleets are now taking fish away from poorer African coastlines (hey – we've already fished out our own shores, so lets do it somewhere else as well). And when the fish stocks go, so do the jobs. Just take the example of the cod collapse in the Grand Banks in Canada: 40,000 people suddenly without work.

Is this smart? Is this clever? Nope. But it is really a spectacular own goal.

Find out more about overfishing

> Next, coming in at No.3: Toxics and pollution