Got an Invasive Army of Crayfish Clones? Try Eating Them

This story was originally published on The Guardian.

The small, bluish-gray, and speckled marbled crayfish is easy to overlook. If it is not already there, it will be coming to a pond or river soon. The all-female freshwater crustacean has become a focus of fascination for scientists in recent years due to its unique ability to clone itself and quickly adapt to new environments, as well as the fact that it has spread.

A biology student bought a bag of crayfish from American traders at a pet fair in Germany in 1995 and named them Texas crayfish. After they started becoming a burden to their new owner due to their rapid rate of reproduction, he distributed them to friends who dumped them into rivers, lakes, and toilets from which they spread rapidly throughout Germany, much of mainland Europe, and most profusely, the island.

When he first came across the creatures, called marmorkrebs, he was astonished by their ability to reproduce from a single cell, like cancer tumors.

He says on the video call that all marbled crayfish have the same genome. They adapt to different environments in a hurry, which makes them scientifically remarkable and similar to a tumor, which also adjusts to its environment.

The genome study led to the discovery that all marbled crayfish originate from a single female. They reproduce without sex. The all-female crustaceans were given a species name in 2015.

In the course of his research, he recalls driving with his students to a lake. He says they waited until it got dark, then suddenly they emerged in their hundreds and thousands. We put them in buckets with a hand net. It was very exciting. We started experimenting with eating them and found them to be quite tasty.

The more we eat, the better.

The authorities in Germany have adopted a strict approach to the marbled crayfish.

Klaus Hidde, a retired bank clerk turned hobby fisher, was tasked by the Berlin senate's environment department last year with setting traps for the crayfish, which have been found in two lakes on Berlin's western fringes. The crayfish are in danger of killing off native species and can also carry a disease called the crayfish plague, which wiped out the European market 150 years ago.