Bottom trawling—dragging heavy nets across the seafloor—has long been known to destroy fragile marine habitats such as coral reefs, seagrass beds, and juvenile fish nurseries. Emerging studies reveal a startling climate impact: carbon-rich sediments disturbed by trawling release CO₂ into the water column, with 55–60% of that carbon returning to the atmosphere within 7–9 years, exacerbating global warming.
Key Highlights
Habitat devastation: Bottom trawling damages over 1.4 million km² of seabed annually, equivalent to 5% of continental shelf area.
Carbon resuspension: Disturbance of blue carbon sediments releases up to 0.16 gigatonnes of CO₂ per year globally.
Atmospheric flux: 55–60% of trawled sediment carbon returns to the atmosphere within 7–9 years, matching annual aviation emissions.
Biodiversity loss: Destruction of corals, sponges, and seagrass reduces biological carbon sequestration by 20–30% in affected areas.
Policy imperative: Calls for trawl-free zones, gear restrictions, and marine protected areas to preserve blue carbon and maintain ocean health.