A 100-fold upsurge in human-produced plastic garbage in the ocean is altering habitats in the marine environment, according to a new study led by a graduate student researcher at Scripps Institution of Oceanography at UC San Diego.

In 2009 an ambitious group of graduate students led the Scripps Environmental Accumulation of Plastic Expedition (SEAPLEX) to the North Pacific Ocean Subtropical Gyre aboard the Scripps research vessel New Horizon. During the voyage the researchers, who concentrated their studies a thousand miles west of California, documented an alarming amount of human-generated trash, mostly broken down bits of plastic the size of a fingernail floating across thousands of miles of open ocean.

At the time the researchers didn't have a clear idea of how such trash might be impacting the ocean environment, but a new study published in the May 9 online issue of the journal Biology Letters reveals that plastic debris in the area popularly known as the "Great Pacific Garbage Patch" has increased by 100 times over in the past 40 years, leading to changes in the natural habitat of animals such as the marine insect Halobates sericeus. These "sea skaters" or "water striders"—relatives of pond water skaters—inhabit water surfaces and lay their eggs on flotsam (floating objects). Naturally existing surfaces for their eggs include, for example: seashells, seabird feathers, tar lumps and pumice. In the new study researchers found that sea skaters have exploited the influx of plastic garbage as new surfaces for their eggs. This has led to a rise in the insect's egg densities in the North Pacific Subtropical Gyre.

Such an increase, documented for the first time in a marine invertebrate (animal without a backbone) in the open ocean, may have consequences for animals across the marine food web, such as crabs that prey on sea skaters and their eggs.