Larval Swimming and Feeding Modes: Effects on Flow Structures and Particle Transport

Despite the widely recognized ecological importance of benthic invertebrates and their larvae, the role of their small-scale locomotion, which is critical for feeding success and predator avoidance, has not been well characterized. Our study reveals a unique behavioral trait in Semibalanus balanoides nauplii, the ability to alternate between distinct swimming and feeding modes. This research investigates how these behaviors affect surrounding flow structures, particle transport, and ultimately, the selective ingestion of particulate matter. We quantify (1) larval survival when exposed to various particulate types, (2) flow structures generated by larval motion using micro-PIV (3) trajectories of algae and microplastics across a range of particle sizes, and (4) larval responses to different particulate compositions to evaluate ingestion selectivity.

The goal of this study is to determine whether flow structures generated by larval locomotion contribute to species-specific particle selectivity. By characterizing how larval motion influences surrounding particle transport and ingestion, we aim to establish a mechanistic link between feeding behavior, flow dynamics, and species-specific responses to various types of particulate matter. These insights will improve our understanding of the preferred particle size ranges consumed by different benthic invertebrate larvae, contributing to a better understanding of the marine food web. In addition to natural food sources such as algae, this research will also provide insights on how microplastic exposure may differentially impact larval survival across species, particularly in relation to their ability to selectively ingest or exclude harmful particles.