Gooseneck barnacles (Lepas spp.) ingest microplastic debris in the North Pacific Subtropical Gyre.

Deborah S Goodwin,Miriam C Goldstein

doi:10.7717/peerj.184

Abstract

Substantial quantities of small plastic particles, termed “microplastic,” have been found in many areas of the world ocean, and have accumulated in particularly high densities on the surface of the subtropical gyres. While plastic debris has been documented on the surface of the North Pacific Subtropical Gyre (NPSG) since the early 1970s, the ecological implications remain poorly understood. Organisms associated with floating objects, termed the “rafting assemblage,” are an important component of the NPSG ecosystem. These objects are often dominated by abundant and fast-growing gooseneck barnacles (Lepas spp.), which predate on plankton and larval fishes at the sea surface. To assess the potential effects of microplastic on the rafting community, we examined the gastrointestinal tracts of 385 barnacles collected from the NPSG for evidence of plastic ingestion. We found that 33.5% of the barnacles had plastic particles present in their gastrointestinal tract, ranging from one plastic particle to a maximum of 30 particles. Particle ingestion was positively correlated to capitulum length, and no blockage of the stomach or intestines was observed. The majority of ingested plastic was polyethylene, with polypropylene and polystyrene also present. Our results suggest that barnacle ingestion of microplastic is relatively common, with unknown trophic impacts on the rafting community and the NPSG ecosystem.

Highlights

Oceanic litter, termed “marine debris” or “plastic pollution,” is a matter of increasing scientific and public concern (STAP, 2011; US Environmental Protection Agency, 2011; Secretariat of the Convention on Biological Diversity and the Scientific and Technical Advisory Panel–GEF, 2012)
Of the 385 barnacles examined, 129 individuals (33.5%) had ingested plastic (Fig. 2, Table 1). These included 243 Lepas anatifera and 85 Lepas pacifica (57 barnacles could not be identified to species), of which 90 L. anatifera, 34 L. pacifica, and 5 Lepas spp. contained plastic
Our results show that 33.5% of lepadid barnacles collected from the North Pacific Subtropical Gyre (NPSG) ingested microplastic, and that the sizes and types of ingested particles were approximately representative of microplastic found on the NPSG surface

Summary

Introduction

Oceanic litter, termed “marine debris” or “plastic pollution,” is a matter of increasing scientific and public concern (STAP, 2011; US Environmental Protection Agency, 2011; Secretariat of the Convention on Biological Diversity and the Scientific and Technical Advisory Panel–GEF, 2012). The durability and longevity that make plastic a useful substance leads to its persistence in the marine environment, with consequences that include entanglement, damage to habitats, species transport, and ingestion (National Research Council, 2008). Negative effects of plastic ingestion may include intestinal blockage, diminished feeding stimulus, lowered steroid hormone levels, delayed ovulation and reproductive failure (Azzarello & Van Vleet, 1987; Derraik, 2002). Because oceanic plastic debris can contain high levels of hydrophobic toxins (Endo et al, 2005; Frias, Sobral & Ferreira, 2010; Rios et al, 2010; Rochman et al, 2013), ingestion of plastic debris may increase toxic exposure (Teuten et al, 2009; Gassel et al, 2013)

Methods

Results

Conclusion