Protecting the Deep Sea

Far below the surface of our oceans lie entire mountain ranges covered with ancient corals and unusual creatures. Although we once thought the deep sea to be barren, scientists now understand that it is teeming with life, including many species found nowhere else. Scientists estimate that as many as 10 million species inhabit the deep sea, comprising biodiversity comparable to the world’s richest tropical rain forests.

But recent advances in bottom trawl technology also make it possible to fish the deep sea's mountain peaks, canyons, and seabed. Stronger engines, bigger nets, and advanced navigational tools, and fish-finding electronics allow vessels to drag nets across the ocean’s floor as deep as 2 kilometers (1.2 miles). This enables well-capitalized fleets of bottom trawlers from a handful of wealthy nations to roam the high seas, destroying some of the planet's last and most ecologically rich frontiers in search of dwindling numbers of fish and crustaceans.

Fragile deep-sea habitats that have taken centuries to grow are destroyed within hours by these bottom trawlers. Commercially valuable catch ends up in fish markets, restaurants, and even school lunches, while everything else is discarded. Most of the species that are caught reproduce slowly. For example, orange roughy can live for more than 100 years and only start reproducing between ages 23 and 40. The deep sea is also home to remarkably rich coral systems. Once thought to inhabit only warm, shallow waters of tropical and subtropical regions, corals appeared to have been thriving in deep, dark, and cold waters throughout the world for millions of years. Indeed, it is now thought that there are more coral species living at great ocean depths than in tropical shallows.

Carbon dating of living cold-water coral reefs has revealed that the oldest may have existed for more than 8,000 years. Several of the coral species create complex reefs and ornate, forest-like structures that rival tropical coral systems in their size and complexity. In fact, the oldest and tallest reef yet observed is 35 meters high, about 114 feet. It will take hundreds of years, if not longer, for these deep-sea ecosystems to recover from destructive fishing methods.

The U.N. General Assembly has called on all fishing nations to manage fish stocks sustainably and to protect vulnerable marine ecosystems from destructive fishing practices, including bottom trawling. The North Atlantic is the most heavily bottom- trawled area in the world and is exploited mainly by the fishing fleets of the European Union. The Pew Charitable Trusts, a member of the Deep Sea Conservation Coalition, is calling on the EU and other states fishing in the North Atlantic to abide by the General Assembly’s resolutions, to which they have all unanimously agreed, and to support the proposal from the European Commission to phase out the EU’s fleet of deep-sea bottom trawlers.

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