Marine fish harvests are adversely affected by a combination of anthropogenic and natural/climatic stressors. Per current fisheries science understanding, direct human exploitation (overfishing) is regarded as the most immediate and severe driver of fish stock decline, followed by chronic habitat degradation from pollution, then longer-term climate change impacts on ocean productivity and species distribution, with episodic natural climate oscillations like El Niño causing comparatively more localized/periodic impacts.
Current fisheries science ranks overfishing as the dominant and most direct threat to marine fish harvests globally, as it directly removes biomass faster than stocks...
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