I'm thrilled that Congressman Hefley has the vision to safeguard some of America's finest marine areas. We know that trawling has effects on the seabed that are similar to the effects of clearcutting in forests, yet the area of seafloor trawled worldwide each year is 150 times greater than the area clearcut. This legislation is a crucial first step in addressing this global problem by focusing on a few key areas in US waters and requiring NMFS to document impacts of trawling in them. Dr. Norse and Dr. Les Watling of the University of Maine coauthored a landmark study published in the December 1998 issue of the scientific journal Conservation Biology that showed severe impacts of trawling on the seafloor and estimated the area trawled annually. The study concluded that mobile fishing gear causes the largest physical disturbance of the world's seabed.
Bottom trawls are large, weighted nets that are towed behind boats or ships.
They kill marine organisms by crushing, burying and exposing them to predators. Trawling also reduces the structural complexity of habitats and eliminates nursery areas. Seabed habitat features such as rocky reefs, boulders, cobbles, sponges and worm tubes are necessary for the survival of many marine species, including juvenile fish. These complex structures provide places for feeding and hiding from predators. Not only do these natural features provide cover for commercially important species such as cod and lobster, but also for their prey, which includes sea urchins, crabs, small crustaceans, and marine worms.