Inorganic contamination in roadkill birds in Northeast Brazil

Wildlife roadkill surveys in Brazil often focus on birds, as they are one of the main groups affected by road accidents. In addition roadkill, anthropogenic litter also contributes to a significant number of bird fatalities every year. The present study aimed to investigate the stomach contents and possible contamination by inorganic material of birds killed on a federal highway that crosses the Serra de Itabaiana National Park in the state of Sergipe, Brazil. Monitoring and data collection were carried out from January to June 2022, with a motorcycle at an average speed of 60 km/h. The collected animals were transported to the Institute of Technology and Research, located at the Tiradentes University, Sergipe, Brazil, and a plastic material was identified. The plastic material found was subjected to Fourier Transform Infrared Spectroscopy (FTIR), which showed a similar wavenumber to a polymer in the polypropylene chain, very common in plastic packaging. The presence of plastics and metals in the intestinal contents of Caracara plancus and Crotophaga ani is noteworthy, as they have a greater tendency to ingest plastics due to their generalist diet. Plastic contamination in Progne chalybea and Nyctidromus albicollis probably occurred through bioaccumulation, from the consumption of insects contaminated by microplastics.