World

Large increase in plastic waste in north-east Pacific Ocean

21:59 pm on 9 May 2012

The quantity of small plastic fragments floating in the north-east Pacific Ocean has increased a hundred fold in the past 40 years.

Scientists from the Scripps Institution of Oceanography documented the big rise when they trawled the waters off California.

This Scripps study follows another report by colleagues at the institution that showed 9% of the fish collected during the same Seaplex voyage had plastic waste in their stomachs.

That investigation, published in Marine Ecology Progress Series, estimated the fish at intermediate ocean depths in the North Pacific Ocean could be ingesting plastic at a rate of roughly 12,000 to 24,000 tonnes per year.

Sunlight and the action of the waves will degrade and shred the material over time into pieces the size of a fingernail, or smaller.

The BBC reports an obvious concern is that this micro-material could be ingested by marine organisms, but the Scripps team has noted another, perhaps unexpected, consequence.

The fragments make it easier for the marine insect Halobates sericeus to lay its eggs out over the ocean.

These "sea skaters" or "water striders" - relatives of pond water skaters - need a platform for the task.

Normally, this might be seabird feathers, tar lumps or even pieces of pumice rock. But it is clear from the trawl results that H. sericeus has been greatly aided by the numerous plastic surfaces now available to it in the Pacific.