Microplastics are persistent environmental contaminants that have been recently documented in numerous ecological systems. Microplastics were documented in the gastrointestinal (GI) tracts of terrestrial raptors in central Florida in 2018. We derived microplastic isolation protocols from that study to populate a baseline dataset of microplastics in the GI tracts of terrestrial raptors on the central coast of California. From January through August 2021, raptor carcasses were donated to our project by Pacific Wildlife Care, a wildlife rehabilitation clinic in Morro Bay, CA. Sixteen carcasses were examined: three Red-Tailed Hawks (Buteo jamaicensis), four Red-Shouldered Hawks (Buteo lineatus), two Great Horned Owls (Bubo virginianus), and seven Barn Owls (Tyto alba). We found trace amounts of microplastics in the GI tracts of all sixteen individuals, with a mean (± SE) of 12.25 (± 1.89) microplastic particles per bird. Of the total of 196 microplastic particles we observed, microfibers were the most abundant (58%), followed by microbeads (34%) and microfragments (8%). Our future research aims to utilize micro-Fourier spectroscopy to identify polymers from this baseline dataset. The ecological and physiological implications of microplastics upon these species are unclear and warrant further study.

Alexis Leviner is a graduate of California Polytechnic State University - San Luis Obispo with a B.S. in Animal Science and a minor in Biology. During her undergraduate education she participated in a variety of research, including population surveys of northern elephant seals, reproductive surveys of seabirds, and comparative animal nutrition analysis. After attending her first Western Section Annual Meeting in 2020, she developed a great interest in wildlife disease, ecotoxicology, and pathology. This ultimately led to her work with Dr. John Perrine, where she spearheaded the microplastics project. She ultimately aspires to pursue a career related to those disciplines.