Threat of plastic pollution to seabirds is global, pervasive, and increasing

Abstract

Plastic pollution in the ocean is a global concern; concentrations reach 580,000 pieces per km 2 and production is increasing exponentially. Although a large number of empirical studies provide emerging evidence of impacts to wildlife, there has been little systematic assessment of risk. We performed a spatial risk analysis using predicted debris distributions and ranges for 186 seabird species to model debris exposure. We adjusted the model using published data on plastic ingestion by seabirds. Eighty of 135 (59%) species with studies reported in the literature between 1962 and 2012 had ingested plastic, and, within those studies, on average 29% of individuals had plastic in their gut. Standardizing the data for time and species, we estimate the ingestion rate would reach 90% of individuals if these studies were conducted today. Using these results from the literature, we tuned our risk model and were able to capture 71% of the variation in plastic ingestion based on a model including exposure, time, study method, and body size. We used this tuned model to predict risk across seabird species at the global scale. The highest area of expected impact occurs at the Southern Ocean boundary in the Tasman Sea between Australia and New Zealand, which contrasts with previous work identifying this area as having low anthropogenic pressures and concentrations of marine debris. We predict that plastics ingestion is increasing in seabirds, that it will reach 99% of all species by 2050, and that effective waste management can reduce this threat.extinction | ingestion | marine debris | risk analysis | seabird

Regional differences in plastic ingestion among Southern Ocean fur seals and albatrosses

“…Attempts to review and model the incidence of plastic ingestion by marine organisms (e.g. Schuyler et al, 2015;Wilcox et al, 2015) depend critically on negative as well as positive records of plastic ingestion. We strongly encourage researchers to report all records of organisms checked for debris ingestion, irrespective of whether any debris is found or not.…”

“…There is mounting concern about the pervasive nature of plastic in the diets of marine organisms, and recent reviews highlight the growing proportions of species affected by this problem (Kühn et al, 2015;Wilcox et al, 2015). Plastic ingestion is widespread in seabirds, but the incidence (frequency of occurrence) and average plastic load per individual (by number and mass) varies considerably among species in relation to the balance between the rates of ingestion and regurgitation-excretion, as well as regional differences in exposure to plastic debris at sea (Ryan, 2015).…”

Using Numerical Model Simulations to Improve the Understanding of Micro-plastic Distribution and Pathways in the Marine Environment

“…Ocean circulation models can further be used to identify where oceanic accumulation zones are most likely to occur. Coupling such tools and approaches with species distribution maps and other ecological information, we can combine disparate data types to predict or identify hotpots of risk to taxa or geographic regions of interest (Schuyler et al, 2013(Schuyler et al, , 2015Wilcox et al, 2015Wilcox et al, , 2016. We can also identify movement pathways or trajectories , identify hotspots, and develop scenario analysis tools to identify potential sources and sinks.…”

“…Dynamically modeling the risk or impacts becomes critically important not only for individuals and populations, but also for marine species that are exposed to multiple threats to survival and persistence. Identifying key geographic regions and taxa at higher or lower threat from marine plastics (e.g., Schuyler et al, 2015;Wilcox et al, 2015) can provide a useful lever to drive policy.…”

Feeding ecology, isotopic niche, and ingestion of fishery-related items of the wandering albatross Diomedea exulans at Kerguelen and Crozet Islands

“…They included plastic fragments, bait remains, and hooks/snoods. Plastic pieces are common in stomach contents of seabirds (Wilcox et al 2015), and they are more frequent in Diomedea species than in smaller albatrosses (Jimé -nez et al 2015). Wandering albatross chicks from Kerguelen and Crozet Islands contained low plastic loads in their stomach, which contrasts with the higher loads of albatross chicks from the North Pacific (Auman et al 1998, Young et al 2009) and minimizes potential deleterious mechanical and physio logical effects from plastic consumption.…”