Debris piles up in Northwest islands
By Jan TenBruggencate
Advertiser Science Writer
Marine debris, most of it plastic, continues to entangle and choke marine life across the Northwestern Hawaiian Islands, despite massive cleanup efforts by the government.
Biological field camp workers on six of the islands and atolls counted eight endangered Hawaiian monk seals entangled in nets this summer. One of them, a pup, died. The others, including both pups and adults, either got themselves free or were released with human help.
And on the open sea, researchers aboard the catamaran Alquita found plastic in each of some 30 fine-mesh trawls they conducted—both on the surface and as deep as 100 feet down. They found jellyfish-like creatures that had bits of plastic inside them, and they found colonies of marine life living with drifting plastic.
The scope of the problem is breathtaking. A five-month effort, sponsored by the National Marine Fisheries Service and the National Ocean Service, yesterday returned to Honolulu with a containerload of nets collected off the Northwestern Hawaiian Islands reefs.
It's the fifth year of the debris cleanup program, and this year divers collected 100 tons of plastics. It included fishing net, fishing line, trawl net, rope and other debris that snags on the reefs, where it rips up sections of coral reef and entangles marine life.
Some areas of the reef were so trashed that divers counted 172 pieces of net per square kilometer.
Mary Donohue, principal investigator for the project, said Hawaiian islands get so much debris because they are situated in a part of the Pacific near an immense floating field of debris.
"We have the worst possible situation. Hawai'i is very near what the oceanographers call the Western Garbage Patch, an area of the sea surface where anything and everything floating in the North Pacific Ocean accumulates due to sea surface currents," she said. "This patch meanders with the seasons and years, and often intersects Hawai'i, leaving our beaches and coral reefs strewn with rubbish originating from throughout the Pacific Rim."
At times, big chunks of tangled ropes and netting get caught on the outer reefs, where storms pound the debris. The chunks break, ripping up coral, and snags again in a new location.
"We found that the outside of the reefs had more plastic than inside. It means that the reefs are becoming sieves" that entrap marine debris as it drifts by, said Michael Bailey, a photographer and marine protection activist who was aboard the Alguita during an ocean survey Sept. 1 to 23.
The ship, carrying dolphin and marine debris researchers, hauled fine-mesh nets through the ocean on mile-long trawls.
"We found plastic debris in every trawl that we did," Bailey said. They also found bits of plastic inside and attached to the bodies of salps, which are small oceanic, transparent, filter-feeding animals. These creatures are near at the bottom of the food chain, and the plastics they contain may give off dangerous chemical byproducts as they degrade, he said.
Onshore, the National Marine Fisheries Service this year had 17 researchers in field camps on Kure Atoll, Midway Atoll, Pearl and Hermes Atoll, Lisianski Island, Laysan Island, and French Frigate Shoals. The field teams are assigned to monitor population trends and track reproduction of the endangered seal population.
"There was at least one case of a monk seal entanglement on each island," said Bud Antonellis, chief of protected species for the fisheries service.
The threat to marine life has led to an annual debris cleanup involving public agencies and private conservation groups.
This year, 24 divers worked throughout the summer. They lived aboard a fishing vessel, and the debris they collected was loaded onto a cargo vessel.
The dive teams collected 100 tons of nets and other debris. That doubles the total take of 100 tons recovered in the previous four years of cleanup.
The plastic netting was to be hauled and processed with the help of Horizon Waste Services and Hawai'i Metals Recycling, and burned in Honolulu's H-POWER plant, where it was expected to produce enough electricity to replace 6,000 gallons of oil.
"Removing marine debris from our precious coral reefs improves fishing, saves endangered seals and turtles, protects the coral reefs and reduces the chance that noxious exotic species will ride debris into Hawaiian waters and wreak havoc with our indigenous species," Donohue said.
Reach Jan TenBruggencate at jant@honoluluadvertiser.com or (808) 245-3074.
