Study shows human garbage is altering marine ecosystems on a large scale
By Summit Voice
SUMMIT COUNTY — Scientists have known for years that a significant portion of society’s plastic debris ends up in the oceans, including the so-called great Pacific garbage patch about 1,000 miles west of California.
Most of the plastic is broken down into tiny fingernail-sized pieces, and the amount of plastic garbage has increased 100-fold in just the past 40 years.
Now, in the first empirical sign that the plastic is changing ocean habitats on a large scale, researchers from the Scripps Institution of Oceanography at UC San Diego documented an increase in sea skater populations, a pelagic marine insect that normally lays its eggs on naturally occurring flotsam including seashells, seabird feathers, tar lumps and pumice.
The Scripps study shows that the 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.
“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,” said Scripps graduate student Miriam Goldstein, lead author of the study and chief scientist of SEAPLEX, a UC Ship Funds-supported voyage. “We’re seeing changes in this marine insect that can be directly attributed to the plastic.”
The sea skaters are relatives of the common freshwater pond skaters. An increase in their population could have consequences for other animals in the food chain, including crabs, which feed on sea skaters and their eggs.
The latest Scripps study follows a report published last year showing that nine percent of the fish collected during a sampling mission 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.
Researchers with the Instituto Oceanográfico in Brazil published a report that eggs of Halobates micans, another species of sea skater, were found on many plastic bits in the South Atlantic off Brazil.
“Plastic only became widespread in late ’40s and early ’50s, but now everyone uses it and over a 40-year range we’ve seen a dramatic increase in ocean plastic,” said Goldstein. “Historically we have not been very good at stopping plastic from getting into the ocean so hopefully in the future we can do better.”