The interaction with plastic litter and ocean currents has created ‘The Great Pacific Garbage Patch’, a zone in the Pacific Ocean where plastic particles congregate. The majority of the plastic pollution is in the form of microplastic, small particles less than 5 mm diameter. What effects does the microplastic have on the ecosystem?
A study published by Miriam Goldstein and colleagues in Biology Letters (May 9, 2012, doi: 10.1098/rsbl.2012.0298 ) finds that the microplastic is creating additional habitat for a marine insect, Halobates sericeus, a sea skater. Sea skaters are the marine equivalents of the more familiar water striders found in freshwater.
Halobates sericeus lays its eggs on hard particles floating on the ocean surface. The microplastic increases the numbers of hard particles and is associated with an increase in egg laying and juveniles. Increases in adult populations have not been noted. This may be due to migration of adults or mortality due to predators of the sea skaters.The addition of microplastic changes the nature of the ecosystem. As the concentrations of microplastic continue to increase, it may lead to increases in populations of adult sea skaters and changes in populations of other insects, planst and animals that share the ecosystem.