Depleted Stock

A depleted stock is one whose biomass has fallen well below the level that supports its full reproductive and harvest potential, often below the limit reference point B_lim. Under United States law a stock is declared overfished when its biomass drops below the minimum stock size threshold, which triggers a mandatory rebuilding plan under the Magnuson-Stevens Act, generally targeting recovery within ten years. Depletion follows sustained fishing mortality above F_MSY, recruitment overfishing, or environmental collapse. Recovery requires F cut below F_MSY so surplus production rebuilds the spawning stock toward B_MSY.