Death trap in the deep

In the wee hours one morning in 2006, the trawler Infidel sank off the southern end of Santa Catalina Island, taking several tonnes of squid and a 3,300-kilogram fishing net down with it.

The Infidel came to rest on its keel, about 45 metres under the sea.

But in the turbid currents, the fine-mesh hemp and polypropylene net — about 14 metres high, several hundred feet long and made to last thousands of years — wrapped itself around the wreck and became a deadly snare for marine life.

It has been entangling and killing sea lions, dolphins, sharks and fish ever since, littering the sandy bottom with skulls and bones picked clean by crabs.

Ghost from the past

Recently a team of volunteer scuba divers armed with filet knives and shears began cutting away the danger.

Guided only by flashlights, they sliced off swaths of the netting, which they then attached to inflatable air bags that rose to the surface.

From there, the netting was hauled aboard the 22-metre trawler Captain Jack.

The potentially dangerous mission was organised by Ocean Defenders Alliance, a non-profit marine conservation group based in Huntington Beach, California, and founded by Kurt Lieber.

“It's one of the spookiest things I've ever seen. ... It's a huge vessel encased in a net — anything that swims into it gets trapped in its billows,'' Lieber said.

“The enormity of the task before us is daunting. We have a long way to go.''

The team of seasoned divers included Avalon Mayor Bob Kennedy, owner of Catalina Scuba Luv, and employees of three other scuba stores on Catalina Island.

Also on board were William Cooper, a marine biologist from University of California in Irvine; Tony Christopher, who makes films on nature; and Avalon harbour patrolman Jason Manix.

Captain Jack's owner Mike Hoover allowed the volunteers to use the 200-tonne vessel.

“Catalina is our backyard and we don't want this kind of garbage in it,'' Manix said. Cinde MacGugan, 36, a store manager at Catalina Diver Supply, led a group of team members who sliced off roughly 167 square metres of netting within 30 minutes.

“It was one of the scariest dives in my life. Once you start cutting, visibility drops from nine metres to zero because the water clouds up with particles and tiny creatures that get shaken loose,'' MacGugan said.

“At one point, I was frantically cutting off pieces of netting when one or more was tugged upward by an airbag.

“I looked around and discovered that I was in a kill zone. There were tonnes of bones and a bunch of sea lion skulls by the propeller and a whole shark caught in the fabric.

My fellow divers were close by and had their eyes on me as I backed out into the clear.''

Close calls during a mission

The limit for normal scuba diving is 120 feet beneath the surface. But because of the depth of the wreck and the 20 minutes needed for each dive to hack off appreciable portions of fishing gear, the divers relied on tanks filled with a special mix of nitrogen and oxygen used to decrease their risk of developing decompression sickness.

By mid-afternoon, the team had raised about 800 square feet of netting, which was piled in a corner of Captain Jack's big wooden back deck.

Several children on board plucked a variety of critters — strawberry anemones, sea cucumbers, brittle stars, shrimp, crabs and snails — off the retrieved netting and tossed them back into the ocean.

Kennedy speculated that it would take as many as nine more diving days to retrieve the bulk of the net.

“Worldwide, there are many thousands of derelict killer nets such as this one, abandoned and adrift in the seas,'' said marine biologist Cooper.

“In one case, abandoned fishing gear in Puget Sound was studied for ten years. An estimated 30,000 marine mammals, fish and birds were killed each year in it.''

Shaking his head in dismay, Cooper added, “There seems to be no law when it comes to dumping in the open ocean.''