Scientist Workshop on Bottom Trawling

MCBI was one of the first organizations to examine the deleterious effects of bottom trawling on the world's marine environment by bringing together renowned scientists for this workshop in 1996.

Participants of the bottom trawling workshop

We realized that trawling is the most important source of human-caused physical disturbance on the world's continental shelves. The scientists concluded that, by crushing marine animals and their habitats, trawling greatly reduces structural complexity of the seabed. This harms organisms (including commercial fishes and lobsters) whose early life history stages benefit from complex seabed structures. Trawling also alters seabed biogeochemistry and causes clouds of sediment to rise into the water column, where they can affect processes that depend on water clarity, from photosynthesis to feeding by fishes.

The scientists acknowledged that different places are trawled at very uneven rates, with some spots missed entirely and others being dragged as many as 100 times a year. They recognized that trawling in some places might actually maintain conditions that favor certain commercially fished species, but that in others it likely contributes to declining fisheries. Nonetheless, all bottom trawling alters the seabed.

This workshop resulted in a cover article of the journal Conservation Biology titled “Disturbance of the Seabed by Mobile Fishing Gear: A Comparison with Forest Clear-Cutting”