Study: Plastic found in raptors
Tiny bits of plastic have been found in the guts of Florida’s hawks, ospreys and other raptors, according to a study by a team from the University of Central Florida and the Audubon Center for Birds of Prey in Maitland.
Microplastics, or eroded specks of synthetic rope, fabrics, bags, beverage containers, cosmetics, tires and many other sources, have invaded much of the world’s environment, and scientists are grappling with understanding the health effects.
Researchers suspect that microplastics of many different shapes and chemical contents could be poisonous or fatally disruptive to wildlife in other ways.
“Birds 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,” said Julia Carlin, a UCF biology graduate and lead author of the study’s findings.
UCF has previously documented microplastics ingested by oysters of Central Florida’s Indian River Lagoon. But analyzing raptors was limited by their state and federal protections.
Carlin and UCF biology professor Linda Walters connected with Audubon’s Birds of Prey Center for access to raptors taken there from January to May last year. Those Central Florida birds had died on the way to the center or shortly after arriving.
They examined 63 birds of eight species, using dissecting microscopes and spectroscopy to study digestive systems extending from the esophagus to the large intestine.
With funding sources that included the National Science Foundation, the study’s participants included several other researchers from UCF and Audubon.
The birds were found to contain a combined 1,197 pieces of plastic that were categorized by type: 86 percent were microfibers, 13 percent were microfragments, .7 percent were macroplastics and .3 percent were microbeads.
Most fibers were either clear or royal blue and the types of plastic varied from rayon to polyester.
Of the 63 birds, 28 were redshouldered hawks and 16 were ospreys. The researchers found that with the red-shouldered hawks “microplastics were significantly more abundant.”
That’s notable because the hawks eat small mammals, snakes and amphibians, while osprey feed primarily on fish.
The researchers theorized that hawks may ingest prey that contain microplastics but also may intake plastics directly.
“We have all benefited from the convenience of plastics, but plastics do not go away once produced,” Walters said.