Effects of Gear
Fishing, especially trawling, also has a direct impact on the habitat in which it takes place.
A trawl beam may weigh a tonne or more. As it is dragged across the seabed, it ploughs up soft bottom substrates and leaves destroyed bottom structures behind.
Soft bottoms host many organisms, such as filter-feeding mussels, brittlestars and polychaete worms recycling decaying organic matter. Many fish live close to the bottom, such as flatfish, rays and skates. Hard, rocky bottoms are also full of life, with hard and soft corals, sponges and algae living attached to the substrate and providing living and hiding space for fish, shellfish, crustaceans and many other organisms.
A single trawl run across a hard or soft bottom may destroy the habitat for many species. As cold-water corals and many other organisms grow very slowly, it may take them many years to recover when disturbed.