Plastic ingestion by marine fish is widespread and increasing

Abstract

Plastic pollution has pervaded almost every facet of the biosphere, yet we lack an understanding of consumption risk by marine species at the global scale. To address this, we compile data from research documenting plastic debris ingestion by marine fish, totaling 171,774 individuals of 555 species. Overall, 386 marine fish species have ingested plastic debris including 210 species of commercial importance. However, 148 species studied had no records of plastic consumption, suggesting that while this evolutionary trap is widespread, it is not yet universal. Across all studies that accounted for microplastics, the incidence rate of plastic ingested by fish was 26%. Over the last decade this incidence has doubled, increasing by 2.4 ± 0.4% per year. This is driven both by increasing detection of smaller sized particles as a result of improved methodologies, as well as an increase in fish consuming plastic. Further, we investigated the role of geographic, ecological, and behavioral factors in the ingestion of plastic across species. These analyses revealed that the abundance of plastic in surface waters was positively correlated to plastic ingestion. Demersal species are more likely to ingest plastic in shallow waters; in contrast, pelagic species were most likely to consume plastic below the mixed layer. Mobile predatory species had the highest likelihood to ingest plastic; similarly, we found a positive relationship between trophic level and plastic ingestion. We also find evidence that surface ingestion‐deep sea egestion of microplastics by mesopelagic myctophids is likely a key mechanism for the export of microplastics from the surface ocean to the seafloor, a sink for marine debris. These results elucidate the role of ecology and biogeography underlying plastic ingestion by marine fish and point toward species and regions in urgent need of study.

A Comparison of Microplastic in Fish From Australia and Fiji

“…Methods used for detection of microplastic have varied over time, with improvements in technical abilities since microplastic research has increased in popularity (Savoca et al, 2021). Some researchers used only naked-eye (e.g., Forrest and Hindell, 2018) or microscope detection (e.g., Cannon et al, 2016) to visualize the gastrointestinal tract content.…”

“…Microplastic ingestion in marine fish is well documented (Markic et al, 2019;Sequeira et al, 2020;Savoca et al, 2021), with field studies reporting microplastic ingestion in wild-caught fish of both commercial and non-commercial interest from a broad range of trophic levels, habitats and benthic zones (Foekema et al, 2013;Nadal et al, 2016;Murphy et al, 2017;Baalkhuyur et al, 2018;Burkhardt-Holm and N'Guyen, 2019;Garnier et al, 2019). Despite this, the literature surrounding microplastic in fish sold through seafood markets and supermarkets is limited.…”

“…In this study, we investigate the abundance and type of plastic found in the gastrointestinal tracts of a suite of species of fish captured and sold for human consumption in two regions of the South Pacific (Australia and Fiji) with distinct economic development levels and waste management strategies. In doing so, we provide essential information on microplastic contamination in fish from a vastly understudied region (Markic et al, 2019;Savoca et al, 2021), which can be used as key baseline data for future studies to monitor the presence and patterns in microplastic type and abundance in the South Pacific. Overall, the extent of microplastic contamination in commercially sold fish from the South Pacific is unknown, as are the types of plastics and polymers present, and how they compare among different sized countries, regarding landmass, population, economy and waste management strategies.…”

Shedding Light on Deep-Sea Biodiversity—A Highly Vulnerable Habitat in the Face of Anthropogenic Change

“…Microplastics have been found in the guts of amphipods in the hadal zone, and even in the deepest trench in the ocean, the Mariana trench, all studied amphipods had ingested microplastics (Jamieson et al, 2019). In addition, Choy et al (2019) found that the concentration of microplastics in the water column, measured down to 1,000 m, was highest between 200 and 600 m. Mesopelagic lanternfishes were recently shown to have high levels of plastic ingestion and their diel migration is likely an important transport mechanism for the plastic particles into the deeper waters (Savoca et al, 2021).The ingestion of plastics has a host of negative effects that are likely to impede health of the individual animals, with incumbent effects on biodiversity (Browne et al, 2013;Deudero and Alomar, 2015;Fossi et al, 2018).…”

Untangling Tales of Tropical Sardines: Local Knowledge From Fisheries in Timor-Leste

“…Detrimental impacts on fish populations have been shown to result from noise disturbance and pollution from small motor boats (Whitfield and Becker, 2014). However, while plastic ingestion by marine fish, including those of commercial importance, is increasing globally, there is no evidence as yet of negative effects on fish populations (Lusher et al, 2017;Savoca et al, 2021). Small pelagic fisheries in Timor-Leste are orders of magnitude smaller than the major sardine fisheries elsewhere in the region-the entire national fisheries production (all species) was estimated to be under 2,500t in 2017 (López-Angarita et al, 2019).…”