Microplastic transfer from the American horseshoe crab to shorebirds through consumption of horseshoe crab eggs in Jamaica Bay, NY

Microplastic transfer between horseshoe crabs (Limulus polyphemus) and migratory shorebirds through con-sumption of crab eggs was examined in Jamaica Bay, New York. Fertilized and unfertilized crab eggs, shorebird fecal pellets, beach sand, and bay water were processed with a hydrogen peroxide solution to remove organic material, then stained with a Nile Red to identify microplastics using fluorescence microscopy. Microplastics were present in all samples and ranged from approximately26-1300 mu m. Unfertilized and fertilized eggs con-tained significantly higher numbers of microplastic particles per gram than shorebird fecal pellets, beach sand, and bay water. The presence of microplastics in unfertilized egg samples indicates that microplastics undergo maternal transfer during oogenesis. We estimated that 1 g of horseshoe crab eggs could contain approximately 426 to 840 microplastic particles, suggesting that shorebirds feeding on this resource could be ingesting a substantial burden of microplastics during their migratory stopover, much of which appears to be retained by shorebirds, rather than being eliminated in their fecal pellets.

Automated summary

Microplastic transfer between horseshoe crabs and migratory shorebirds through consumption of crab eggs was examined in Jamaica Bay, New York. Microplastics were found in all samples, with unfertilized and fertilized eggs containing significantly higher numbers than shorebird fecal pellets, beach sand, and bay water. The presence of microplastics in unfertilized eggs suggests maternal transfer during oogenesis. Shorebirds feeding on horseshoe crab eggs could be ingesting a substantial burden of microplastics, most of which appears to be retained rather than eliminated.