Behavioral and demographic responses of the predatory rotifer Asplanchna sieboldii (Leydig, 1854) fed prey (Plationus patulus (Müller, 1786)) previously exposed to cadmium and microplastics

We quantified the feeding behavior (encounter, attack, capture and ingestion) and demographic parameters (survival and reproduction) of the predatory rotifer Asplanchna sieboldii fed on the prey Plationus patulus previously exposed to microplastics (MPs), Cd or their combination. As compared to controls, capture and ingestion rates of P. patulus by A. sieboldii decreased by 71 and 61%, respectively, with prey previously exposed to mixed MPs and Cd treatment. Life table data showed that the predator died earlier in controls than when fed on prey exposed to both Cd and microplastics. Regardless of the prey treatment, the offspring production by A. sieboldii increased as the available prey numbers increased (from 1 to 4 ind. ml⁻¹). Compared to controls, the fecundity rate of the predator decreased when contaminated prey was offered as food.