Nearly all deep-sea fisheries were found to be unsustainable, and marine scientists have called for putting an end to commercial fishing in the Earth's largest ecosystem.
While only 1% of the world's seafood is supplied from the deep sea, bottom-trawling causes significant and lingering damage to fishes and life on the seafloor like corals, which can otherwise live for as long as 4,000 years.
Including the documentation of the endangered deep-sea fishes around the globe, a group of marine ecologists, fisheries biologists, economists, mathematicians and international policy experts pulished a comprehensive analysis titled Sustainability of Deep-sea Fisheries in the journal Marine Policy.
According to the study, the vast majority of deep-sea fisheries are unsustainable.
The slow pace of the scarce life in the deed sea is overwhelmed by fast-developing and powerful fishing technologies.
Because these fish grow slowly and live a long time, they can only sustain a very low rate of fishing, said Selina Heppell, a marine fisheries ecologist at Oregon State University. On the high seas, it is impossible to control or even monitor the amount of fishing that is occurring. The effects on local populations can be devastating.
Certain deep-sea species such as orange roughy and Chilean sea bass have become popular targets of fishers, and their catch has increased sevenfold from 1960 to 2004, according to the U.N. Food and Agriculture Organization.
Some fish even more than a mile deep.
Fifty years ago no one ate orange roughy, said author Dr. Daniel Pauly, a fisheries biologist with the University of British Columbia.
In fact, it used to be called slimehead, indicating no one ever thought we would eat it. But as we've overfished our coastal species, that changed and so did the name.
The deep sea is the world's worst place to catch fish, said marine ecologist Dr. Elliott Norse, the study's lead author and President of the Marine Conservation Institute in Bellevue, Washington. Deep-sea fishes are especially vulnerable because they can't repopulate quickly after being overfished.
According to Norse, deep-sea fishers can be sustainable only where the fish can multiply rapidly and fisheries are small-scale and use gear that doesn't destroy fish habitat.
With slow-growing fish, there's economic incentive to kill them all and reinvest the money elsewhere to get a higher return-on-investment. Killing off life in the deep sea one place after another isn't good for our oceans or economies. Boom-and-bust fisheries are more like mining than fishing, said Norse.
The scientists called for stricter rules on deep-sea fishing to ensure that fisheries aren't depleted. They suggested that the fisheries be governed by highly precautionary rules, as well as a special management body, and that they be supported with the appropriate data and information.
Since most of the deep-sea fishing waters are international, the scientists also suggested that individual countries manage their vessels and people.
Instead of overfishing the Earth's biggest but most vulnerable ecosystem, nations should recover fish populations and fish in more productive coastal waters, said Norse. Deep-sea fishes are in deep trouble almost everywhere we look. Governments shouldn't be wasting taxpayers' money by keeping unsustainable fisheries afloat.
The study was published just before the United Nations decides whether to continue permitting deep-sea fishing in international waters, or high seas.