"Deep-Sea Corals Are Perhaps the Most Vulnerable to Bottom Trawling of All Forms of Marine Life."
Danson, Ted, Earth Island Journal
Deep-sea corals, found off all coasts of North America, are the ancient forests of the oceans. These beautiful living colonies are extremely slow-growing--less than an inch a year--and some may be thousands of years old. The corals are spawning and nursery grounds for many commercial fish and other marine life, and provide young fish with shelter from predators.
The destructive bottom trawling gear used in many commercial fisheries is the most widespread human threat to deep-sea corals. A simple examination of common bottom trawling gear reveals its destructive potential. Trawl nets, which may stretch 40 feet or more in height and spread over 200 feet wide, are dragged between heavy trawl doors weighing as much as five tons each, bulldozing across the sea floor. Trawls capture virtually everything in their path, including targeted and untargeted fish, marine mammals, turtles, sponges, and deep-sea corals.
With the advent of ever more powerful engines, mapping, navigational and fish finding electronics, and stronger, lighter synthetic materials, bottom trawlers can now operate to depths of 6,000 feet. Using coral-crushing roller and rockhopper gear on their nets, trawlers can fish in deep-sea canyons and over rough seafloor, once avoided because of the damage they caused to nets. Some 40 percent of the world's trawling grounds are now deeper than the edge of the continental shelf and are on the slopes and in the canyons of the continental margins and on seamounts, where most of the world's known deep-sea coral communities are found.
A recent study by the National Academy of Sciences found that over the past decade, more than 231,000 square miles of seafloor off the US coast--roughly the size of California--has been directly affected by bottom trawling. The National Marine Fisheries Service estimates that in Alaskan waters alone, more than a million pounds of corals and sponges are removed from the seafloar every year by commercial fishing, roughly 90 percent by bottom trawlers. …