A new study from the 麻豆原创 has confirmed and quantified, for the first time, the presence of microplastics in terrestrial and aquatic birds of prey in Florida, including hawks, ospreys and owls.
Microplastics are small plastic pieces 鈥� less than the size of a pencil tip 鈥� that come from larger pieces of plastic, such as synthetic clothes, or that are made small for use in health and beauty products or industrial purposes.
The research, which was published online recently in the journal , is important because birds of prey are critical to a functioning ecosystem. The accumulation of microplastics in their digestive systems could lead to poisoning, starvation and death.
鈥淏irds of prey are top predators in the ecosystem and by changing the population or health status of the top predator, it completely alters all of the animals, organisms and habitats below them on the food web,鈥� says Julia Carlin, the study鈥檚 lead author and a graduate of 麻豆原创鈥檚 .
Microplastic contamination of the environment likely began not long after the first piece of plastic was discarded, says Linda Walters, a Pegasus Professor in 麻豆原创鈥檚 Department of Biology and study co-author.
Ingestion of large pieces of plastic by animals was first noted in the 1960s, and an increased focus on microplastic ingestion started around 2010, she says.
Past studies have documented increasing amounts of microplastics in the guts of fish, marine birds, and filter-feeding invertebrates, such as oysters. There have also been recent reports of whales dying from eating dozens of pounds of plastic, including plastic bags. However, birds of prey have not been thoroughly examined before, partly due to their protected status.
Carlin and Walters were able to overcome this by working with the Audubon Center for Birds of Prey in Maitland, Florida, a rehabilitation center that helps injured raptors.
With the center鈥檚 permits, 麻豆原创 researchers were able to examine the stomach contents of 63 birds that were dead when they arrived at the center or died 24 hours after they arrived. The birds were collected from throughout Central Florida.
Using dissecting microscopes and spectroscopy, the researchers found microplastics in the digestive systems of all birds examined, with nearly 1,200 pieces of plastic pulled from the 63 birds.
The most common types of microplastic in the birds were microfibers, which accounted for 86 percent of the plastics found. Microfibers can come from synthetic ropes or clothing and may end up in ecosystems through wastewater from clothes-washing machines.
Blue and clear microplastics were the most common colors identified, but the reasons for this could range from these being the dominant colors of the plastics in the landscape to birds confusing these colors with appropriate prey or nesting materials, according to the study.
Walters says some solutions to the problem could be removing plastic from open landfills, carefully discarding plastic trash, buying natural fabrics instead of plastic-based ones, and retrofitting water treatment plants and stormwater drains to capture microplastics.
鈥淲e have all benefitted from the convenience of plastics, but plastics do not go away once produced,鈥� Walters says.
Study co-authors included Casey Craig, a master鈥檚 student in 麻豆原创鈥檚 Department of Biology; Samantha Little, a raptor-clinic technician with the Audubon Center for Birds of Prey; Melinda Donnelly, an assistant research scientist in 麻豆原创鈥檚 Department of Biology; David Fox, a doctoral candidate in 麻豆原创鈥檚 ; and Lei Zhai, a professor with 麻豆原创鈥檚 Nanoscience Technology Center and Department of Chemistry.
The research was funded by the National Science Foundation, the and the Department of Biology at the 麻豆原创, and the Audubon Center for Birds of Prey.
Carlin is now a doctor of veterinary medicine student at North Carolina State University. She conducted the research as her honors in the major thesis and received the 麻豆原创 Outstanding Honors in the Major Thesis Award this spring for the project.
Walters has a doctorate in biology from the University of South Carolina and a secondary appointment to 麻豆原创鈥檚 . She joined 麻豆原创鈥檚 Department of Biology, part of 麻豆原创鈥檚 , in 1997.
