Growing up near coastal California, 17-year-old Marci watched plastic litter enter the ocean at an alarming rate. After reading about how this debris affected large vertebrates, she wondered how animals lower on the food chain fared.
Marci decided the water strider species Halobates sericeus would be the ideal subject for her experiment. “Since these fully pelagic water striders live solely at the sea-air interface, their life is played out completely on the two-dimensional surface of the ocean,” where most plastic debris collects, wrote Marci in her essay Effect of Neustonic Microplastic Debris on the Pelagic Insect Halobates sericeus. Her experiment earned her a 2011 Young Naturalist Award.
Marci focused her efforts on the North Central Pacific Gyre, a region of rotating ocean currents in the Pacific where plastic collects. She analyzed samples that had been obtained by running a net along the surface of the ocean during cruises. By comparing modern-day samples with those collected during the last 40 years, Marci could look for changes in the abundance of water striders and plastic.
Her results showed a significant increase in the number of the water striders and plastics in the Pacific Gyre over time. While Marci’s data did not prove that the plastic caused the insect numbers to swell, she hypothesizes that the plastic litter might in fact provide the striders with more surfaces for egg laying. On the other hand, oceanographic factors could explain the increase, since strong water currents may cause the insects and debris to collect in one area.
Marci hopes to continue her research by examining plastic’s toxicological effects on water striders as well as the oceanography of the area from which the samples were taken. In the meantime, she plans to study neuroscience at the University of California at Los Angeles, where she is a first-year student this fall.
The Young Naturalist Awards is a nationwide, science-based research contest for students in grades 7 through 12 presented by the Museum. To learn more and to submit your own project, visit amnh.org. The deadline for the 2012 contest is March 9, 2012.
The Young Naturalist Awards are proudly supported by Alcoa Foundation.