Overfished

Overfished is a term used in fisheries management to describe a fish stock whose population size or reproductive capacity has fallen below levels considered sustainable. In most frameworks, a stock is deemed overfished when its biomass or spawning stock biomass (SSB) is below a defined reference point, such as Bmsy (the level associated with maximum sustainable yield). Overfished status can result from prolonged overfishing, but it can also be influenced by environmental variability, habitat degradation, and changes in recruitment.

Indicators of an overfished stock include assessments that estimate current biomass relative to targets, a decline in spawning stock biomass, or fishing mortality that exceeds allowed limits. These signals often trigger rebuilding plans or management changes designed to restore abundance to sustainable levels.

The consequences of being overfished can be substantial. Reduced stock size lowers potential yields and can threaten the livelihoods of fishing communities, while ecosystem effects may include disrupted predator–prey relationships and changes in marine habitat dynamics. Economic and food security impacts can extend beyond the fishing sector when a stock is slow to recover.

Management responses focus on rebuilding abundance through precautionary and adaptive measures. Common tools include catch limits or quotas, seasonal or area closures, gear restrictions, bycatch reduction strategies, and effort controls. In some cases, marine protected areas or broader ecosystem-based management approaches are employed to support recovery. International cooperation, stock assessments, and transparent reporting by regional fisheries management organizations and national authorities underpin these efforts. Concrete outcomes vary by stock and region, with some populations successfully rebuilt and others still requiring ongoing measures.