A Ventura-based research vessel and divers in a miniature submarine this week retrieved 2 1/2 tons of lost scientific equipment that had been snared in a net with a 50-foot shark and swept from Santa Monica Bay to the 1,000-foot-deep ocean floor off of Anacapa Island.
Recovery of the equipment--a set of sophisticated devices used to record the direction and speed of ocean currents--adds "irreplaceable data" to a U.S. Department of Energy study of marine ecosystems, said Barbara Hickey, a University of Washington oceanographer in charge of ocean measurements for the study.
Meanwhile, removal of 600 to 800 linear feet of pink plastic netting from the Channel Islands National Marine Sanctuary will save the lives of the fish and sea mammals that it would have trapped, said Lt. Cmdr. Francesca M. Cava, manager of the sanctuary, which spans 1,252 square miles in the Santa Barbara Channel.
Cava said entanglement in cast-off nets kills many sea animals, pointing to 30,000 seals lost each year in the Pribilof Islands near Alaska. The nets do not disintegrate, so the destructive "ghost-fishing" continues for years, she said.
The Wm. A. McGaw chugged into its home port of Ventura on Sunday afternoon with the net, the equipment, the remains of the long-dead basking shark, and hundreds of other sea creatures dead and alive.
"It was as if you'd taken a bunch of string and twirled it around a pencil," said Jeff Kirby, chief engineer of the vessel, owned by Ocean Enterprises Ltd. of Santa Barbara. Half a dozen crew members hacked away at the netting to extricate the equipment, which was flown to Seattle on Monday.
On Tuesday, Hickey said the information it had recorded was undisturbed.
She said the instruments' 40-mile journey to a spot off the Ventura coast should not fuel fears that some of the sewage pumped by Los Angeles into Santa Monica Bay makes the same trip.
The currents that propelled the 5,000 pounds of equipment come no closer to the coast than 10 miles, she said, while outfalls from Los Angeles sewage plants are no more than about 5 miles offshore, where sewage accumulates on an underwater shelf.
Hickey, who said she keeps Los Angeles sewage-treatment officials up to date on her research, said it will take at least a year to analyze the data that she has collected about the nature of currents in Santa Monica Bay.
The recovered equipment, worth about $60,000, recorded subtle shifts in surface currents every 30 minutes. A 12-foot tower chronicled changes in the wind. As many as 15 such packages have been operating at various spots off the California coast as part of a 6-year government effort to find out what happens when wastes from onshore energy operations filter into the sea, Hickey said.
The set of instruments retrieved Sunday had disappeared in May, 1987, 6 weeks after Hickey and her group--the California Basins Study Program--had anchored the equipment about 10 miles off Santa Monica.
Government scientists now theorize that the equipment became tangled in a net that had been cut loose by a Soviet fishing vessel. The net, whose weave is uniquely Russian, had snagged a huge shark that the fishing boat was too small to hoist aboard. So, the theory goes, the net was cast adrift and, at some point, net, shark and scientific equipment became yoked.
Not until May did Hickey and her team have any inkling that they might discover the missing devices. A civilian crew working for the Pacific Missile Test Center had spotted the equipment's marker buoy about 3 miles off Anacapa Island. But crew members, unable to haul up the cable attached to the buoy, simply cut the buoy off and brought it ashore.
At that point, Hickey said, scientists alerted by the Navy believed that the buoy had drifted north with the currents, but the payload was somewhere on the bottom of Santa Monica Bay. They hired two small submarines--including the famous Alvin that explored the Titanic--to search for it, but found only a 3-foot-deep gouge where the devices' 3,500-pound anchor had been dragged off.
After they learned that the marker buoy was not merely floating near Anacapa, but had been detached, the scientists rushed back to the Santa Barbara Channel. They located the equipment by listening for the faint signals it still emitted, and contracted with Ocean Services and with Marfab, a Los Angeles company that provided a two-man submarine.
A retrieval effort in September ended when a chain broke just as the equipment was being lifted out of the water. Another attempt Nov. 17 was canceled because of heavy seas.