First detection of plastic microfibers in a wild population of South American fur seals (Arctocephalus australis) in the Chilean Northern Patagonia

Investigating Microplastic Presence Amongst Grey Seals (Halichoerus Grypus) of the North Sea

“…Given that each lter paper analysed represented 44.4 % of the initial mass of the faecal subsample, we estimate an average microplastic abundance within these individuals to be 0.81 particles per gram of dried scat. Contrary to other studies reporting both particle number per scat 18,22,33 and per gram of wet scat 18 , we consider particle number per gram of dried scat to be a robust 'relative measure' -an 'index' independent of original scat sample weight, and a useful way to present the detection rate data, as it accounts for variation in scat mass and water content. However, microplastic egestion rates in grey seals are unknown, and thus whether plastic particles would be intermittently or continually shed remains unknown.…”

“…Owing to their small size, microplastics are bioavailable for ingestion by a range of marine fauna including; seabirds 14 , sh 15 , invertebrates 16 and marine mammals 17,18 . For mammalian species, microplastic ingestion has been hypothesised to occur unintentionally during prey capture in microplastic-polluted areas, particularly during lter feeding 19,20 .…”

“…For mammalian species, microplastic ingestion has been hypothesised to occur unintentionally during prey capture in microplastic-polluted areas, particularly during lter feeding 19,20 . Furthermore, indirect microplastic consumption following the ingestion of microplastic-contaminated prey, termed trophic transfer, and this has been proven to occur under captive conditions 21 and is widely speculated to occur in natura 17,18,22 .…”

“…Although several papers report the presence of microplastics amongst marine mammals 5,17,19,[30][31][32] , research typically relies on necropsies performed on stranded or by-caught individuals 33 -providing few occasions to study anthropogenic contaminants 32 and with relatively small sample sizes from individuals that have died, and may have been feeding abnormally pre-mortem 12 . Alternatively, scat analysis offers the opportunity to obtain data on microplastic exposure in live, wild and free-ranging pinnipeds through a non-invasive and humane manner 18,21 . This could permit the analysis of larger sample sizes, which may provide more representative estimates of microplastic pollution amongst wider populations 12 .…”

Plastic ingestion, retention, and transport in animals from the eastern Canadian Arctic

“…The ingestion of macroplastics appears to be less common for pinnipeds, suggesting that these animals could be less likely to encounter larger plastic debris during feeding. A summary of a selection of studies that have reported macroand/or microplastic pollution in the GITs of marine mammals is provided in Eriksson and Burton, 2003;McMahon et al, 1999;Nelms et al, 2018;Perez-Venegas et al, 2018), Donohue et al (2019) demonstrates the exposure of these seals to microplastic pollution, and suggests the use of faecal collection as a potential non-invasive way of monitoring microplastic pollution exposure in some marine mammals. However, a potential challenge with this method is that it may not always be possible to discern between plastic particles in the scat with those originating from atmospheric deposition (Dris et al, 2016).…”