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Threat Profile

Overfishing

Fishing pressure that outpaces a stock's ability to reproduce — now affecting more than a third of the world's assessed fisheries, unevenly across regions.

Published May 2026 Last reviewed July 2026 Evidence level Very strong Reading time 6 min

Overview

A fish stock is overfished when it is harvested faster than it can reproduce and rebuild its population. The world's most comprehensive assessment to date — covering 2,570 individual stocks, informed by over 650 experts across more than 200 institutions in over 90 countries — gives the clearest picture yet of where global fisheries actually stand.

Established fact

64.5% of assessed global fish stocks are fished within biologically sustainable levels; 35.5% are classified as overfished. Overfishing has been rising by roughly 1 percentage point per year on average in recent years.

Source: FAO, Review of the State of World Marine Fishery Resources, 2025

Weighted by actual catch volume rather than stock count, the picture looks somewhat better: 77.2% of global landings come from biologically sustainable stocks, since well-managed, high-volume fisheries account for a large share of total catch.

Where It's Worst — and Where It Isn't

Sustainability varies enormously by region and fishery type, which is itself informative: it shows overfishing is a management outcome, not an inevitability.

Antarctic
100%
NE Pacific
92.7%
SW Pacific
85%
Global average
64.5%
Deep-sea species
29%

Share of stocks fished within biologically sustainable levels, by region/category. Source: FAO, 2025.

Established fact

In the Antarctic, 100% of assessed stocks are fished sustainably — attributed to ecosystem-based management and international cooperation, in direct contrast to deep-sea fisheries, where only 29% meet the same standard.

Source: Marine Stewardship Council; FAO, 2025

Documented Impacts

Stock depletionPopulations fished beyond their reproductive capacity decline over time, reducing both future catch and the ecological role the species plays.
BycatchUnintended species caught alongside target fish make up roughly a quarter of total marine catch and are typically discarded, often fatally — highly migratory sharks caught in tuna fisheries are a particular concern.
Food-web disruptionRemoving key predator or prey species at unsustainable rates can cascade through marine food webs, changing the abundance of unrelated species.
Editorial analysis

The regional gap here is the most useful part of the data: it's direct evidence that overfishing is a solvable management problem, not an unavoidable consequence of fishing itself. Where enforcement, quotas and international cooperation exist — the Antarctic and Northeast Pacific being the clearest cases — sustainability rates approach or reach 100%. Where governance is weak or absent, as with many deep-sea fisheries, sustainability collapses.

Uncertainty & Evidence Gaps

Stock assessments for well-studied, high-value fisheries (tuna, major groundfish stocks) are high-confidence, built on decades of catch and survey data. Deep-sea and data-poor fisheries carry much greater uncertainty, since many are assessed with limited survey coverage — meaning the true share of overfished deep-sea stocks could be underestimated rather than overestimated.