The North American signal crayfish is a great threat to Scotland’s native fish and other freshwater wildlife.
The lobster-like animal is a voracious predator and competes for space in rivers and lochs with native fish, particularly juvenile salmon and trout. They also cause great damage by burrowing into spawning beds and riverbanks.
They are very resilient and will voluntarily leave the water to travel over land in search of food or a new habitat.
Find out what canoeists, boaters and anglers should do to help prevent the spread of this invasive species. It’s illegal to return to the water a live signal crayfish, even if caught by accident. The booklet explains what to do if this happens, and who to contact to report any sightings.
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