Swordfish Catching Technique Could Be Banned to Protect Other Marine Life

Leatherback sea turtles like this one are vulnerable to entanglement and drowning in drift gillnets. | Photo: Reiner Kraft/Flickr/Creative Commons License

A bill that would ban the practice of setting so-called "drift gillnets" to capture sharks and swordfish off the California coast will be the topic of discussion in a meeting of a crucial Assembly committee Tuesday.

Assembly Bill 2019, introduced in February by Assembly Member Paul Fong, would ban the use of drift gillnets in California waters due to what opponents call an unacceptably high level of harm the nets cause to marine mammals, sea turtles, and other non-target wildlife.

Drift gillnets used off the California coast are nylon mesh that can legally be up to 6,000 feet long and reach 200 feet deep. Set at night primarily to catch Pacific swordfish, though thresher sharks are an important secondary target, the nets are suspected to kill as many as 138 marine mammals each year off California along with an unknown number of critically endangered sea turtles. And the Assembly's Water, Parks, and Wildlife Committee is set to discuss whether the state should phase them out in favor of swordfish capture methods that do less damage to other wildlife.

As currently worded, Fong's bill, co-written by fellow Assembly members Marc Levine and Mark Stone, would require swordfishers to use other means such as hand-held hook-and-line rigs or hand-thrusted harpoons to haul swordfish out of the water. The ban would become effective in February.

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If it's passed, AB 2019 would bring California's gillnet laws in line with those in Oregon and Washington, both of which states forbid the use of drift gillnets in their territorial waters. The United Nations enacted a moratorium on drift gillnet fishing in international waters in 1993, and that moratorium is still in effect.

Drift gillnet use in California waters isn't completely unregulated. Since 2001, the gear has been illegal to use between August 15 and November 15 in the Pacific Leatherback Conservation Area, which runs from Point Sur north to the Oregon line, and 200 miles offshore. The restriction area was designated to protect the leatherback sea turtle, which migrates through the area during the closure period. Before the ban, at least 112 leatherbacks were known to have died in drift gillnets: since the ban, that number has dropped to two.

Using the nets is also prohibited throughout the state's 200-mile economic zone from February 1 thorough April 30, and within 75 miles of shore between May 1 and August 14. For the most part, driftnetting for swordfish is really only done between August and January off the Southern California coast, and that's for a fish that many environmentally concerned consumers don't eat anyway. The Environmental Protection Agency and Food and Drug Administration urge that pregnant women and young children avoid eating swordfish because of its high levels of mercury, and many consumers understandably confuse Pacific swordfish with the more imperiled North Atlantic swordfish, the subject of environmentalist PR campaigns in the late 1990s urging diners to order something else.

Marine conservation groups backing a drift gillnet ban say that the gear, which has only been in use for swordfish since the 1980s, must be relegated to the past to protect wildlife. "The use of drift gillnets off California is a failed 30-year experiment that must come to an end," said Dr. Geoff Shester of the group Oceana when AB 2019 was introduced in February. "It's time for California to remove these destructive nets that result in the senseless and cruel taking and killing of over 100 marine mammals every year."

That's not necessarily an opinion shared across the board: The Monterey Bay Aquarium's Seafood Watch checklist describes Pacific swordfish caught in drift gillnets in California as a "good alternative," though it does list line- or harpoon-caught California swordfish as a better choice. And some observers have made the argument that further closing the California swordfish fishery just shifts demand to less-well-regulated fisheries in waters where U.S. wildlife law cannot be enforced.

But given the declining popularity of swordfish among diners, a ban is likely close to a foregone conclusion. And it's hard to argue with measures to protect our state's non-target marine wildlife. "The driftnet fishery for swordfish is California's deadliest catch," said Teri Shore, Program Director at Turtle Island Restoration Network, another backer of the bill. "The driftnet fishery kills more marine mammals than any other along the West Coast. It's time to end use of driftnet gear."

For ongoing environmental coverage in March 2017 and afterward, please visit our show Earth Focus, or browse Redefine for historic material.
KCET's award-winning environment news project Redefine ran from July 2012 through February 2017.

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