Centipedes, woodlice, and slugs are among the most commonly encountered invertebrates in British gardens, yet their potential to experience suffering is rarely considered. Evidence suggests more complexity than is commonly assumed.
The welfare significance of centipedes, woodlice, and slugs is genuinely uncertain, but the precautionary principle applies. Slug killing methods vary greatly in humaneness — salt application causes a slow osmotic death that, if aversion to damaging stimuli reflects suffering, may involve significant pain. Iron phosphate pellets represent a more humane and ecologically safer alternative. Woodlice, as crustaceans, benefit from the growing scientific recognition that decapods and other crustaceans deserve welfare protection — a principle the UK Animal Welfare (Sentience) Act 2022 extended to decapods. Applying consistent ethical standards across these creatures is intellectually demanding but morally significant.