All about ablation

The Fish Society | 29.01.2023

Eyestalk ablation is an obscure aspect of prawn farming that is beginning to attract public attention. Here's our take.

Many decades ago at the dawn of the prawn farming industry, it was discovered by prawn hatcheries (which sell prawn larvae to prawn farms for growing on) that if a female prawn had one of its eyestalks chopped off, it would lay ten times more eggs. It immediately became standard practice in prawn hatcheries to carry out what is known as eyestalk ablation (using a pair of scissors, one prawn at a time).

It's brutal but can't be wished away. What's our attitude?

A couple of years ago we had a serious attempt at selling prawns untainted by ablation. We tracked down and launched a line of organic prawns from a small farm which grows its own larvae in a 100% natural way. These prawns were of excellent quality on many benchmarks, but the price was high, sales were low and the supply was unreliable. We would still have these prawns on sale if we could obtain them and we hope to reintroduce them in due course.

So the farmed prawns we currently sell are all from farms using hatcheries practising eyestalk ablation, because at least 99% of prawn farms use such stock.

Pressure to eliminate the practice is accelerating. Several years ago, a new EU standard for organic prawns forbade ablation. Although few if any farms signed up to that initiative (becuase organic is expensive in every way), it was a start. Last year GlobalGAP, which is one of the big three standard setters in fish farming announced that from 2024 it will not certify farms using larvae of prawns which have suffered ablation. Soon after, the Aquaculture Stewardship Council - a similar body (but in fish farming, much bigger) - acknowledged that ablation is an issue it needs to address.

So far the other big standard-setter, the Global Aquaculture Alliance, has not laid out such plans but intriguingly, it recently awarded an Innovation prize to a researcher at Stirling University whose work, according to the Alliance, "debunked the conventional notion that eyestalk ablation results in higher egg production".

Let's all keep our fingers Xd.