Contents lists available at ScienceDirect Marine Pollution Bulletin journal homepage: www.elsevier.com/locate/marpolbul Incidence of marine debris in seabirds feeding at different water depths D.C. Tavares a,⁎ , J.F. de Moura b , A. Merico b,c , S. Siciliano d a Laboratório de Ciências Ambientais, Universidade Estadual do Norte Fluminense, Campos dos Goytacazes, RJ, Brazil b Systems Ecology, Leibniz Centre for Tropical Marine Research, Bremen, Germany c Physics & Earth Sciences, Jacobs University, Bremen, Germany d Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, RJ, Brazil ARTICLE INFO Keywords: Plastic Pollution Marine birds Ocean South Atlantic Ocean Tropical ecology ABSTRACT Marine debris such as plastic fragments and fishing gears are accumulating in the ocean at alarming rates. This study assesses the incidence of debris in the gastrointestinal tracts of seabirds feeding at different depths and found stranded along the Brazilian coast in the period 2010–2013. More than half (55%) of the species analysed, corresponding to 16% of the total number of individuals, presented plastic particles in their gastrointestinal tracts. The incidence of debris was higher in birds feeding predominantly at intermediate (3–6 m) and deep (20–100 m) waters than those feeding at surface (< 2 m). These results suggest that studying the presence of debris in organisms mainly feeding at the ocean surface provides a limited view about the risks that this form of pollution has on marine life and highlight the ubiquitous and three-dimensional distribution of plastic in the oceans. 1. Introduction The accumulation of debris in the oceans raises concerns about the effects that this form of pollution can have on the abundance and diversity of marine life (Derraik, 2002; Moore, 2015; Tavares et al., 2016a; Thompson et al., 2004; Wilcox et al., 2015). Plastic comprises up to 97% of marine debris and its production and use is expected to increase, especially among emerging economies (Ryan, 2014). The ingestion of debris has noxious effects on marine organisms, these include starvation due to the ingestion of non-energy return items, damage of gastrointestinal tracts (Di Beneditto and Awabdi, 2014; Petry et al., 2008; Ryan, 1987a), and contamination by persistent organic pollutants such as polychlorinated biphenyls (PCBs) and polybromi- nated diphenyl ethers (PBDEs) (Colabuono et al., 2010; Ryan et al., 1988; Tanaka et al., 2013). Current estimates about the amount of plastic in the ocean surface range between 7000 and 35,000 tons (Cózar et al., 2014). These quantities, however, are inconsistent with the staggering estimates of 4.8 to 12.7 million tons of plastic that entered the oceans just in 2010 (Jambeck et al., 2015). This discrepancy suggests that a large amount of debris sinks into the ocean interior (Li et al., 2016; Van Cauwenberghe et al., 2013; Woodall, 2014). A growing body of literature demonstrates that organisms feeding below the water surface ingest debris (Corcoran et al., 2015; Di Beneditto and Awabdi, 2014; Possatto et al., 2011; Romeo et al., 2015). Although the problem of plastic ingestion has been studied in different seabird species, information on diving birds is relatively less common than on birds foraging at surface (Bond et al., 2013; Brandão et al., 2011; Codina-García et al., 2013; Provencher et al., 2010). Seabirds are good model organisms for assessing the threats posed by this form of pollution below the ocean surface and for obtaining indirect indications about the distribution of debris in the water column because different species of seabirds feed at different depths (Avery- Gomm et al., 2013; Schreiber and Burger, 2002). Assessing the impact of marine debris at and below the surface of the oceans is time consuming, logistically difficult, and very expensive. Alternatively, data from stranded seabirds can be highly valuable for evaluating the severity of marine pollution through the water column (Ryan et al., 2009). Carcasses found washed onshore can be easily collected and at relatively low costs (Camphuysen and Heubeck, 2001; Ryan et al., 2009), a particularly convenient form of sampling, especially for emerging countries such as Brazil. The aims of this study are to (1) evaluate the incidence of marine debris in the digestive tracts of a comprehensive number of seabird species found washed ashore in the coastal areas of Brazil, and (2) test the possibility that the incidence of debris found in the digestive tracts depends on the predominant feeding depths of the birds. We expect that species feeding at surface are more likely to ingest debris compared to those feeding below the surface (Avery-Gomm et al., 2013; Provencher et al., 2014; Ryan, 1987a). This work is important because, although it http://dx.doi.org/10.1016/j.marpolbul.2017.04.012 Received 7 February 2017; Received in revised form 6 April 2017; Accepted 8 April 2017 ⁎ Corresponding author. E-mail address: dta@zmt-bremen.de (D.C. Tavares). Marine Pollution Bulletin xxx (xxxx) xxx–xxx 0025-326X/ © 2017 Elsevier Ltd. All rights reserved. Please cite this article as: Tavares, D.C., Marine Pollution Bulletin (2017), http://dx.doi.org/10.1016/j.marpolbul.2017.04.012