Investigation reveals global fisheries are in far worse shape than we thought – and many have already collapsed

When fish are taken from our oceans faster than they can reproduce, their population numbers decline. This over-fishing upsets marine ecosystems. It's also bad for human populations that rely on fish for protein in their diets.

To manage fishing areas sustainably, we need accurate data on how many fish exist and how abundant they will be in future. Fisheries scientists use complex mathematical models to determine this.

But an investigation by my colleagues and I, published today in the journal Science, casts serious doubt on the accuracy of these models.

We studied 230 fisheries around the world. We found ...