American Intruder Lurks In Scottish Streams, Clawed And Hungry
by Ari Shapiro
The story starts in the streams and lakes of the northwestern United States, where North American signal crayfish (Pacifastacus leniusculus) are a familiar sight. Turn over a rock and you may well encounter one.
But in Scottish streams and lochs, these creatures are intruders.
In the United States, we often hear about invasive Asian carp, zebra mussels or snakehead fish from China that take over American waterways. It’s a two-way street: American species are causing chaos in other parts of the world, too.
(In their native North American ecosystems) They eat aquatic insects and larvae; raccoons and herons, in turn, eat them. The system works. But those same crayfish wreak havoc in Scottish waters like Clyde’s Burn — a stream in Scotland where anglers from all over the world come to fish…
(read more: NPR)