Padrões de contaminação por microplásticos em peixes recifais na RESEX-Mar de Arraial do Cabo

Abstract

Despite providing critical ecosystem services to the planet and coastal populations, marine ecosystems have been continually impacted by diverse anthropogenic activities. In this scenario, the ubiquity and small size of microplastics at different geographic scales on marine systems make them one of the most critical pollutants in food webs. The characteristics of plastic debris, associated with the ecological attributes of the species, are important factors influencing ingestion rates, which are still understudied for rocky reefs. This work aimed to comparatively study the environmental contamination and the ingestion of microplastics by different species of reef fishes, analyzing different ecological attributes of fish species on a rocky shore in Arraial do Cabo, RJ. Likewise, microplastics were quantified in environmental matrices (water, epilithic algal matrix EAM- and sediment) to understand the main sources of contamination in the food web. The fish spearfished and immediately taken to the laboratory to remove the gastrointestinal tract to quantify the presence of microplastics. The microplastics found were quantified, measured and classified according to shape and color. The type and quantity of polymers were compared between the pelagic and benthic compartments, and among reef fish species from different trophic groups. MPs were found in all environmental matrices and analyzed species. The largest number of MPs was found in the EAM. Stegastes fuscus and Abudefduf saxatilis were the species with the highest average number of MPs/ind. Body, mouth and intestine size influence the intake of MPs. “Grubbers-excavating” and “nibblers” tend to ingest fewer MPs. We found no significant relationship between trophic level and MP intake. These findings can be applied in management strategies that contribute to the conservation of reef environments.