Assessing the Presence and Concentration of Microplastics in the Gizzards of Virginia Waterfowl

• Main Author: Bustamante, Thomas
• Format: Other/Unknown Material
• Language: English
• Published: Eagle Scholar 2021
• Subjects: Biology; Canada; Branta canadensis; Canada Goose
• Online Access: https://scholar.umw.edu/student_research/417; https://scholar.umw.edu/context/student_research/article/1419/viewcontent/Bustamante_T.B._Thesis.pdf

Microplastics are defined as plastics smaller than 5mm which originate from sources such as manufactured pellets, personal care products, and the breakdown of larger plastic items. They have become a ubiquitous water pollutant, and while a substantial amount of research on their impacts on marine ecosystems has been conducted, the presence of microplastics in freshwater systems and organisms remains less understood. In this study, we assessed the presence and concentrations of microplastic particles in the gizzards of the Canada Goose (Branta canadensis), Longtailed Duck (Clangula hyemalis), Ringneck Duck (Aythya collaris), Mallard (Anas platyrhynchos), and Goldeneye Duck (Bucephala clangula) hunted in the Piedmont and Coastal Plain of Virginia. Gizzards were bisected, then their contents were removed for analysis. Internal gizzard contents were digested in 30% hydrogen peroxide with an iron catalyst, then were density separated in a NaCl saline solution to isolate microplastics. Samples were then visually inspected under a dissecting microscope. After laboratory contamination was taken into account, 53.6% of gizzards contained microplastics. Samples ranged in concentration from 0 to 1.75 plastics/gram of gizzard material. While concentrations did not differ between sex and location, diving ducks had significantly higher microplastic concentrations than Canada Geese. The raw number of microplastics between the two groups was the same. These results provide evidence that freshwater species of waterfowl not only consume microplastics, but also retain them in their digestive tracts. As microplastics continue to release into the environment, more organisms, such as these waterfowl, will consume these plastics and potentially suffer toxicological consequences.