Do whitefish (Coregonus lavaretus) larvae show adaptive variation in the avoidance of microplastic ingestion?. (July 2020)

• Record Type: Journal Article
• Authors: Huuskonen, Hannu; Subiron i Folguera, Joan; Kortet, Raine; Akkanen, Jarkko; Vainikka, Anssi; Janhunen, Matti; Kekäläinen, Jukka
• Is Part Of: Environmental pollution. Volume 262(2020)
• Publication Date: 2020-07
• Subjects: Fish larvae -- Polystyrene -- Microspheres -- Parental effects -- Accumulation -- Elimination; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2020.114353
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: The presence of microplastics in aquatic ecosystems has recently received increased attention. Small plastic particles may resemble natural food items of larval fish and other aquatic organisms, and create strong selective pressures on the feeding traits in exposed populations. Here, we examined if larval ingestion of 90 μm polystyrene microspheres, in the presence of zooplankton ( Artemia nauplii, mean length = 433 μm), shows adaptive variation in the European whitefish ( Coregonus lavaretus ). A full-factorial experimental breeding design allowed us to estimate the relative contributions of male (sire) and female (dam) parents and full-sib family variance in early feeding traits, and also genetic (co)variation between these traits. We also monitored the magnitude of intake and elimination of microplastics from the alimentary tracts of the larvae. In general, larval whitefish ingested small numbers of microplastics (mean = 1.8, range = 0–26 particles per larva), but ingestion was marginally affected by the dam, and more strongly by the full-sib family variation. Microsphere ingestion showed no statistically significant additive genetic variation, and thus, no heritability. Moreover, microsphere ingestion rate covaried positively with the ingestion of Artemia, further suggesting that larvae cannot adaptively avoid microsphere ingestion. Together with the detected strong genetic correlation between food intake and microplastic intake, the results suggest that larval fish do not readily possess additive genetic variation that would help them to adapt to the increasing pollution by microplastics. The conflict between feeding on natural food and avoiding microplastics deserves further attention. Graphical abstract: Image 1 Highlights: Ingestion of 90 μm polystyrene microspheres exhibits no additive genetic variation. Vulnerability to microsphere ingestion is mostly determined by environmental effects. Larvae appeared to ingest microplastics along with zooplankton. Low potential for microplastic intake to evolve independently of food intake. Abstract : The present work provides the first experimental evidence that microplastic feeding tendency in the presence of zooplankton shows no significant additive genetic variation, raising the concern that fish may not be able to adapt to the presence of plastic particles by actively avoiding them in their foraging.