Urban waterbirds shifting microplastics

• Microplastics were detected in fecal samples of Kerala inland waterbirds. • Polyethylene, polypropylene, and polystyrene were the most abundant polymers. • ATR-FTIR analysis enabled precise identification of microplastic types. • Polymer patterns align with foraging habits and local plastic waste profiles. • Spectral bands indicated structural properties of isolated microplastic types. Plastic pollution in aquatic ecosystems poses growing ecological risks, particularly for piscivorous birds occupying higher trophic levels. This study assessed the ingestion and excretion patterns of microplastics (MPs) in two monotypic urban inland waterbird species, the Indian cormorant ( Phalacrocorax fuscicollis ) and the Oriental darter ( Anhinga melanogaster ), from Alappuzha, Kerala, a densely populated region with high urban runoff. Five polymer types were identified through ATR-FTIR spectroscopy, with polyethylene (28.8 %), polypropylene (22.2 %), and polystyrene (20.0 %) being the most abundant, reflecting local plastic waste profiles and bird foraging behavior. The presence of MPs in juvenile and adult individuals suggests potential age-independent exposure pathways and highlights their role as potential biovectors of synthetic debris and associated contaminants. The findings emphasize the need for localized conservation strategies and contribute baseline data for ecological risk assessments. This research aligns with Sustainable Development Goals 6, 12, and 15, advocating for cleaner water systems, sustainable material use, and protection of terrestrial and aquatic biodiversity.