Bottom-Feeders\nEat Their Fiber: Ingestion of Anthropogenic\nMicrodebris by Antarctic Deep-Sea Invertebrates Depends on Feeding\nEcology

Anthropogenic debris\nhas been documented in Antarctica for the\npast 40 years. Upon breakdown, large pieces become microdebris, which\nreaches the seafloor through a variety of physical and biological\nprocesses. The Antarctic benthos, deeply reliant on sinking organic\nparticles, is thus vulnerable to ingesting microdebris. By using benthic\nspecimens sampled between 1986 and 2016 and deposited in biological\ncollections, we provide the first record of microdebris in Southern\nOcean deep-sea invertebrates. Specimens from 15 species (n = 169 organisms)\nhad their gut content examined, with 13 species yielding microdebris\nin the shape of fibers (n = 85 fibers). The highest ingestion percentages\nwere recorded in the sea cucumbers <i>Heterocucumis steineni</i> (100%), Molpadia violacea (83%) and <i>Scotoplanes globosa</i> (75%), and in the brittle star <i>Amphioplus peregrinator</i> (53%). Deposit- and suspension-feeding\nwere the strategies which yielded the most fibers, accounting for\n83.53% of particles. Seven fibers were identified as microplastics,\ncomposed of polyamide, polycarbonate, polyester, polyethylene terephthalate,\npolyisoprene and polysulfone. We also provide the earliest record\nof a microplastic in Antarctica, a polysulfone fiber ingested by a <i>Boreomysis</i> sp. mysid caught in 1986. The occurrence of fibers\nin the world’s most remote continental margin renews concerns\nof pollution in seemingly isolated regions.