Microplastics May Be Accumulating in the Food Chain of Endangered Galápagos Penguins

A new study using model predictions has uncovered a likely rapid accumulation of microplastics around Santa Cruz Island, an island in the Galápagos National Park of Ecuador.

The model predictions point to an accumulation of plastics sized from 1 micron to less than 5 millimeters in waters around the human-populated island. The researchers behind the study evaluated the feces of the Galápagos penguin, an endangered species, and the prey of these penguins.

In addition to analyzing data around Santa Cruz Island, the researchers modeled for broader areas, including the Bolivar Channel Ecosystem and the western areas of the Galápagos Islands, to which the Galápagos penguins are endemic.

The modeling predicted rapid bioaccumulation of microplastics across the food web, with the most microplastics building up in the endangered penguins, then moving down the food web to barracuda, anchovies, sardines, herrings, black-striped salema and zooplankton. The authors published their findings in the journal PLOS ONE.

“The model predictions highlight the accumulation behavior and residence time of microplastics in the gut,” Karly McMullen, first author of the study from the Institute for the Oceans and Fisheries at the University of British Columbia, said in a statement. “With microplastics emerging as a prominent ocean pollutant, entering the environment every day, there is a growing concern for marine fauna and coastal wildlife, particularly if this anthropogenic threat is reaching even the most remote and protected areas such as the Galápagos Archipelago.”

Galápagos penguins are endangered, with an estimate of fewer than 2,000 individuals remaining. According to the World Wildlife Fund, some of the top threats to the species include climate change, bycatch and pollution.

The study authors wrote that plastic pollution is only getting worse, with an estimated 170 trillion plastic particles in the ocean. The model predictions revealed the rising risks of bioaccumulation across food webs. The researchers noted that in their specific study, the Galápagos penguins are “the canary in the coal mine,” revealing that more more research on microplastics and more efforts to reduce microplastics are crucial not just for the Galápagos ecosystems, but global ecosystems.

“The goal of this food web bioaccumulation modeling work was to provide science and data to support risk management of hazardous plastic waste, reduce microplastic emissions in the oceans and marine remote UNESCO Heritage sites such as the Galápagos Islands, and inform local and international marine policy to conserve endangered, endemic seabird species of Galápagos Marine Reserve,” Juan Jose Alava, senior author of the study and principal investigator of the Ocean Pollution Research Unit at the University of British Columbia’s Institute for the Oceans and Fisheries, explained in a statement. “It is imperative that we prioritizing efforts to reduce the input of microplastics into vulnerable ecosystems and food webs, particularly such as that of the endangered Galápagos penguin.”