Scientists from the University of Exeter, Galapagos Conservation Trust (GCT), and the Galapagos Science Center have made a grim discovery on the Island of San Cristobal where Charles Darwin first landed in the Galapagos.
In a new study, published in Science of the Total Environment, the authors describe the discovery of macro and microplastics in all of the marine habitats of the Island, including a beach that’s home to the extremely rare “Godzilla” marine iguana. Plastics were also found in other habits such as rocky lava shores and mangroves on the Island.
“The pristine image of Galapagos might give the impression that the islands are somehow protected from plastic pollution, but our study clearly shows that’s not the case,” Dr Ceri Lewis, of Exeter’s Global Systems Institute, said in a statement. “There are less than 500 Godzilla marine iguanas in existence, and it’s concerning that they are living alongside this high level of plastic pollution.”
Moreover, the findings suggest that only 2% of “macroplastic” (plastic fragments larger than 5 millimeters) identified was coming from the surrounding Islands. Most were brought to the location by ocean currents from elsewhere, the authors suggest. “Our study highlights how far plastic pollution travels, and how it contaminates every part of marine ecosystems,” lead author on the study Dr Jen Jones said.
The scientists also discovered various quantities of microplastics inside different marine invertebrates such as barnacles and urchins, which may result in harm to the local food web. “These animals are a crucial part of food webs that support the larger species that famously live on and around the Galapagos Islands,” Jones added.
Concerning as it already is, Jones and colleagues also identified marine vertebrates that are most at risk of ingesting larger macroplastics or potentially getting entangled in larger items discarded by humans. The animals most at risk were hammerhead and whale sharks, sea lions, and sea turtles living on and off the coastline in the region.
Plastic pollution remains an ever-increasing problem for ecosystems and marine animals. For example, microplastics have now been identified in several marine species, including turtles, though their direct influence on health remains unclear. “The potential health effects of plastic ingestion on marine animals are largely unknown, and more research is needed,” said Jones.
The ocean is riddled with these microscopic particles, whose reach stretches as far out as the sea ice regions of Antarctica, and it isn’t going to go away anytime soon. If we want to prevent a disaster in the years to come, we will have to tackle the pollution head-on and reduce our dependency on plastic before it’s too late.
“Given the level of pollution we have found in this remote location, it’s clear that plastic pollution needs to stop at source. You can’t fix the problem just by cleaning beaches.” Jones concludes.
Read the original release via IFLScience! at https://www.iflscience.com/environment/galapagos-seawater-marine-animals-and-beaches-infested-with-plastic-pollution/ or continue reading below for more details from the recent study.
- Plastic contamination was identified in all marine habitats surveyed in San Cristobal.
- Hotspots for beach plastics are on the eastern coast, up to 449 particles m−2.
- Elevated microplastics in surface seawater around the harbour shows local inputs.
- Microplastics were found in 52% of marine invertebrates sampled (n = 123).
- 27 marine vertebrates scored at high risk of harm from entanglement and ingestion.
Ecuador’s Galapagos Islands and their unique biodiversity are a global conservation priority. We explored the presence, composition and environmental drivers of plastic contamination across the marine ecosystem at an island scale, investigated uptake in marine invertebrates and designed a systematic priority scoring analysis to identify the most vulnerable vertebrate species. Beach contamination varied by site (macroplastic 0–0.66 items·m−2, microplastics 0–448.8 particles·m−2 or 0–74.6 particles·kg−1), with high plastic accumulation on east-facing beaches that are influenced by the Humboldt Current. Local littering and waste management leakages accounted for just 2% of macroplastic. Microplastics (including anthropogenic cellulosics) were ubiquitous but in low concentrations in benthic sediments (6.7–86.7 particles·kg−1) and surface seawater (0.04–0.89 particles·m−3), with elevated concentrations in the harbour suggesting some local input. Microplastics were present in all seven marine invertebrate species examined, found in 52% of individuals (n = 123) confirming uptake of microplastics in the Galapagos marine food web. Priority scoring analysis combining species distribution information, IUCN Red List conservation status and literature evidence of harm from entanglement and ingestion of plastics in similar species identified 27 marine vertebrates in need of urgent, targeted monitoring and mitigation including pinnipeds, seabirds, turtles and sharks.
Read the remainder of the study via Science Direct at https://www.sciencedirect.com/science/article/pii/S0048969721027753?dgcid=author
Jen S. Jones, Adam Porter, Juan Pablo Muñoz-Pérez, Daniela Alarcón-Ruales, Tamara S. Galloway, Brendan J. Godley, David Santillo, Jessica Vagg, Ceri Lewis,
Plastic contamination of a Galapagos Island (Ecuador) and the relative risks to native marine species,
Science of The Total Environment,
Keywords: Microplastic; Conservation tool; Invertebrate ingestion; Marine litter; Rapid assessment
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