To the casual eye, this may be a fish caught somewhere off the uncanny valley, but most fishes’ limited eyesight will mean that it slips by completely unnoticed as it goes about its business. And its business is detecting hazardous pollutants in the water off the coast of Spain.

They’ve been designed by a group of UK scientists with the intention of not scaring the local water life. They look like carp, and move around realistically with a top speed of around 2.25mph. They cost £20,000 a-piece, but fortunately the designers from the University of Essex have found the European Commission happy to foot the bill.