concept

Potential biological removal

A quota rule that replaced maximum sustainable yield, built specifically for marine mammals after the older approach failed. Instead of the best-guess estimate of population size it uses a conservative lower-bound estimate; instead of taking the full productivity it takes half; then it multiplies by a recovery factor dropped very low for an endangered stock. The result is a number far smaller than maximum sustainable yield, and that is the intent: when each individual lost takes decades to replace, the error should fall on the animal's side rather than the quota's. The quiet shift here is from asking "how much can be taken" to asking "what happens if we are wrong".