Green crabs are highly invasive in North America and Australia, causing ecological damage requiring management, while also being explored as an aquaculture species — raising welfare questions in both contexts.
Green crab welfare in invasive species removal programmes involves the killing of sentient animals for ecological conservation purposes. The welfare trade-off is justified by the ecological damage caused to native species and their habitats. However, applying welfare principles to the killing methods used in removal programmes — preferring rapid killing over prolonged dying in traps — is compatible with the conservation goal while reducing suffering. Aquaculture of green crabs for commercial use as food or bait raises the same welfare concerns as other live crustacean trade, requiring the same precautionary welfare standards.