We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Microplastic ingestion by three copepod species with contrasting feeding strategies along an environmental gradient in the Gulf of Thailand
Summary
Tiny ocean creatures called copepods—a key food source for fish—are eating microplastics regardless of their feeding style, with what's available in their local water seeming to matter more than how they hunt for food. Since these copepods are at the bottom of the marine food chain, this suggests the amount of microplastic pollution in an area may be a bigger factor than species behavior in determining how much plastic works its way up to the fish we eat.
Understanding what governs microplastic (MP) ingestion in plankton is essential for assessing exposure in marine food webs. Microplastic ingestion by copepods has been reported worldwide, yet drivers of variability remain poorly understood in tropical systems, particularly the relative weight of feeding traits versus environmental availability. We quantified ingestion rates in three copepod species with contrasting feeding modes across the principal environmental gradient of the upper Gulf of Thailand (GoT), Subeucalanus crassus (passive suspension feeder), Acartia erythraea (flexible suspension/ambush), and Centropages furcatus (cruising–ambush omnivore). MPs occurred in 88.5% of samples, with a mean ingestion of 0.24 ± 0.27 MPs ind⁻¹. Polypropylene (PP) and polyethylene terephthalate (PET) dominated the polymer composition and particles <50 µm prevailed. Ingestion did not differ significantly among species despite their contrasting feeding strategies. Polymer composition and particle size distribution clustered by site rather than by species, with site-level differences in composition along the environmental gradient. Together, these patterns are consistent with opportunistic feeding and suggest that local environmental availability, rather than feeding trait, may shape what copepods ingest. Confirming this mechanism would require concurrent water-column MP measurements alongside hydrographic context.