The first report of microplastic observation in waterfowl of southern Caspian sea

The term microplastic was first used in ۲۰۰۴ to describe very small plastic particles (۵۰ micrometers) in a column of water and sediment. In ۲۰۰۹, researchers suggested that microplastics should include all parts less than ۵ mm. However, there is currently no universal definition of the size range for microplastics. Microplastics are present in the aquatic ecosystem as a pollutant and pose a threat to the marine environment. In addition to occupying marine environments, these microplastics are also easily eaten by marine organisms. In many types of research, ingestion of microplastic particles by seabirds, especially from the Procellariiformes, has been reported. Ingested parts due to being indigestible can have destructive effects on birds, including: obstruction of the animal's stomach due to its occupation with microplastic particles, deformation, the volume of the gizzard or stomach of the bird, as well as direct death for the animal. For the purposes of this study, in the present study, a total of ۹۵ bird carcasses of Anatidae, Scolopacidae, Rallidae, Podicipedidae, Laridae and Phoenicopteridae were collected. The stomach contents of all birds were described using a scalpel. After this step, their contents were washed with a ۱ mm sieve and then placed in a petri dish. The remaining material was taken under a stereomicroscope and examined for plastic parts. Microplastic was found in ۸۶% of birds. At the species level, ۹۴% of birds ingested at least one type of microplastic. Fragments, fibers and films were the most common type of microplastic observed among birds.