Antarctic krill are fundamental to Southern Ocean food webs and are harvested commercially at massive scale. Their sentience status and the welfare implications of krill fisheries deserve serious consideration.
Krill welfare sits at the frontier of invertebrate welfare ethics — these are small crustaceans whose sentience status is genuinely uncertain, but whose numbers in commercial harvest are so enormous that even a small probability of welfare significance implies vast potential suffering. The precautionary approach that applies to other crustaceans with uncertain sentience applies here too. Krill harvesting involves pumping vast quantities of animals aboard ships where they may be crushed, suffocated, or processed alive. The ecological welfare dimension is equally significant: removing krill at scale from Antarctic ecosystems reduces the food available to recovering whale and penguin populations, creating a welfare cascade through the food web. Marine protected areas around key krill feeding grounds for dependent predators are a welfare intervention as much as an ecological one, protecting the ability of these animals to meet their energetic needs.