Ingestion of polyethylene microspheres occur only in presence of prey in the jellyfish Aurelia aurita

Microplastic ingestion was studied in A. aurita, a bloom-forming, circumglobal medusa. Here, we determined whether factors such as the concentration of polyethylene microspheres (75-90 μm) or the absence/presence of prey affect the ingestion, duration of microspheres in the gastrovascular cavity (time of presence), and retention time. The presence of polyethylene microspheres' was determined by exposing medusae during 480 min to three different treatments (5000, 10,000, 20,000 particles L^-1), and was checked every 10 min to ascertain whether they had incorporated any. Preliminary results show that microsphere ingestion occurred only in the presence of prey (⁓294 Artemia nauplii L^-1). The time of presence of microbeads in A. aurita increased (103, 177, and 227 min), with increasing microplastic concentration, and the microbeads were egested within 150 min. This study initiates the understanding of the potential implications that arise of the encounter between jellyfish and microplastic agglomerates, and with perspectives for future research.