Claire Nouvian is a journalist and filmmaker fascinated by the world’s oceans. She’s got a lot to be interested in – she points out that while 75% of the world’s surface is water, 99% of the world’s volume is water. We’ve explored only 0.5% of the ocean’s surface since the 1960s, and have barely explored the deep seas.
Nouvian is especially interested in the deep seas, locations thousands of meters below the surface. She fell in love in 2001 when she visited the Monterey Bay Aquarium, which had movies of strange and wonderful creates from far below the surface. Monterey is near a very deep cleft in the ocean, which allows researchers to study as deep as 4000 meters below the sea on a daily basis, which is a truly unique opportunity. She was astounded by the animals and dedicated several years to reporting on these creatures in a book and film called The Deep.
There are numerous potential threats to deep sea ecosystems. Many species depend on whale carcasses to support their ecosystems – as the whales die and drop to the floor, they feed hundreds of other species. If whales continue to die off, they’ll affect huge swaths of undersea ecosystems. Other threats include exploration for oil, which now occurs as deep as 2 kilometers, and will likely keep expanding until we’re seeking oil 7 kilometers below the surface. Deep sea mining and dumping have huge effects. CO2 sequestration, which we’re starting to experiment with, may have serious adverse effects on the deep seas, as might attempts to extract methane from the deep sea.
Bottom-trawling, on the other hand, is real and present danger for deep oceans right now, she argues. She’s talking about large trawl nets, 60 to 100 meter-wide openings, with heavy steel doors. They drag across the bottom of the floor and grab everything in their path. This has been a popular fishing technique for years on continental margins. However, we’re getting desperate to find large fish, and she’s concerned that we’ll begin seeing deep sea trawling far offshore.
She quotes Dr. Daniel Pauly, who says,
“We’ve declared war on fish… and we’ve won it.” Fishermen now use military techniques to catch fish, employing tools like GPS, sonar and satellite imaging to catch more efficiently. Our catches have increased fivefold between 1950 and 1990… but we’re also seeing a decline in fishing stock since the 1980s. Now 70% of global fishing stocks are overexploited.
She’s studied the orange roughy closely, travelling with research trawlers in New Zealand. Orange Roughy is especially vulnerable because fish aggregate to spawn. Her trawler accidently dragged in the midst of a roughy “plume”, and caught 7 tons within 20 seconds. Commercial fisherman fill their nets within two minutes, then spend a couple of days processing the catch. Restoring these fish stocks is very challenging – it takes 20 years for these fish to reach sexual maturity, and some of the fish caught are 200 years old. “It’s sort of cannibalistic, like eating my great-grandmother,” she tells us.
She’s at least as worried about sharks, who are routinely caught in these nets – the Atlantic shark population has dropped 95% in the past few decades. As a result, sharks are almost guaranteed to be the next major marine animal to become extinct.
The impact of deep sea trawling is even more dramatic on coral reefs. There is deep sea coral, and it was a major obstacle to deep sea trawling. But new nets destroy coral first, then sweep for species, so that nets don’t get damaged. Literally, nothing is left behind once these nets move through.
Nouvian argues that there’s no social benefit in allowing deep sea trawling. It’s only 0.5% of the worldwide catch, and doesn’t meaningfully impact the world supply of protein. There are only 300 or 400 ships engaged in the business, a $400 million dollar a year industry. “We are destroying a unique, unassessed planetary heritage at unprecedented speed and scale in a probably irreversible manner for no reason,” she says, referring to the phenomenon as an undersea Rwanda. “We could have lifted a finger and intervened but we couldn’t care less.”
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