Eyestalk ablation — removing one eye from breeding shrimp to induce spawning — is standard industry practice with significant welfare implications that are increasingly challenged.
Eyestalk ablation is performed at a scale — hundreds of millions of animals annually — that makes it one of the most numerically significant welfare-relevant practices in aquaculture. The procedure causes tissue damage equivalent to amputation of a sensory organ, and given emerging evidence of shrimp nociception, it is likely painful. The practice persists because no equally effective alternative currently exists at commercial scale — the sinus gland inhibition of maturation is a genuine production challenge. However, this is a problem susceptible to research investment, and the Shrimp Welfare Project and other organisations are actively developing alternatives. Industry willingness to adopt alternatives when they become available, and consumer and regulatory pressure to accelerate research, are the most effective levers for change.