Insects in the Garbage Patch

Plastics in the ocean have increased 100-fold in the past 40 years, creating the Great Pacific Garbage Patch, plus other areas of wide-spread trash in the oceans.

It’s hard to imagine this waste benefitting any marine life. We’ve all seen what it does to albatross. And Ed Yong reports further in Discover that:

Everything eats them [the small plastic bits]: fish, crustaceans, even filter-feeders like mussels and barnacles. They clog up guts and bloodstreams. They leach synthetic chemicals into the environment.

But a new study in Biology Letters finds one sea creature that is happy to have the plastic in their neighborhood: sea skaters.

Sea skaters—relatives of pond water skaters—inhabit water surfaces and lay their eggs on flotsam. Usually these floating objects include seashells, seabird feathers, tar lumps and pumice. But 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 (NPSG).

How will this affect the ecosystem? The researchers say that it could have consequences for animals across the marine food web, such as crabs that prey on sea skaters and their eggs, and the plankton that the sea skaters feed on.

“This paper shows a dramatic increase in plastic over a relatively short time period and the effect it’s having on a common North Pacific Gyre invertebrate” says Scripps Institution of Oceanography graduate student Miriam Goldstein, lead author of the study. “We’re seeing changes in this marine insect that can be directly attributed to the plastic.”

The new study follows a report published last year by Scripps researchers showing that nine percent of the fish collected during a 2009 mission to the NPSG contained plastic waste in their stomachs. That study estimated that fish in the intermediate ocean depths of the North Pacific Ocean ingest plastic at a rate of roughly 12,000 to 24,000 tons per year.

Image: Anthony Smith