Native crayfish species are threatened globally by invasive species and disease. Understanding crayfish welfare and the ecological complexity of their situation informs better conservation choices.
Crayfish welfare sits at the intersection of uncertain sentience and genuine conservation complexity. Killing invasive signal crayfish protects native white-clawed crayfish populations but harms individual signal crayfish. Those individual signal crayfish may have morally relevant experiences — the evidence for crustacean pain is growing. This is a case where the welfare of invasive individuals must be weighed against the welfare of native species populations whose existence is threatened. Welfare-sensitive invasive crayfish management uses the most rapid killing methods and focuses on areas where native crayfish survival depends on control.