Islands that inspired Charles Darwin now drowning in a sea of plastic

Plastic on the Cocos (Keeling) Islands  
Plastic on the Cocos (Keeling) Islands   Credit: Silke Stuckenbrock

The island chain which inspired Charles Darwin’s first major scientific paper is now drowning in a sea of plastic, alarming new images show.

Australia's Cocos (Keeling) Islands, a ring shaped outcrop in the eastern Indian Ocean, was visited by Darwin and the crew of HMS Beagle in 1836, and helped him develop the theory that it was the gradual sinking of volcanic islands which allowed circular coral reefs, or atolls, to form.

On his return to England, he published his first major paper on the theory, and later in his work The Voyage of The Beagle, the pristine sands and palm trees of Cocos were pictured in the drawing entitled ‘Inside an atoll.’

Yet today the islands are littered with refuse, with scientists from the University of Tasmania estimating there are now 414 million pieces of debris on the beaches.

Inside an Atoll, Keeling Island - from Darwin's The Voyage of the Beagle  Credit: First Collection / Alamy Stock Photo 

A study led by marine biologist Dr Jennifer Lavers found 238 tonnes of plastic, including 977,000 shoes and 373,000 toothbrushes. The researchers estimate that 338,355,473 items are buried up to four inches below the surface, 26 times greater than the amount visible on the beaches.

The remote islands have a population of just 529, proving that most of the debris is floating in on ocean currents from more populated areas of the world.

“Plastic pollution is now ubiquitous in our oceans, and remote islands are an ideal place to get an objective view of the volume of plastic debris now circling the globe,” Dr Lavers said.

“Our estimate is conservative, as we only sampled down to a depth of 10 centimetres and couldn't access some beaches that are known debris 'hotspots'.

“Islands such as these are like canaries in a coal mine and it's increasingly urgent that we act on the warnings they are giving us,” said Dr Lavers said.

 Jennifer Lavers with plastic on the islands  Credit: Silke Stuckenbrock  

Darwin spent 12 days on the Cocos (Keeling) Islands, exploring the archipelago and collecting geological, botanical and animal specimens including corals, shells, rocks, plants, fish, insects and crabs which he took back to England, some of which can be viewed at the British Museum and Natural History Museum in London.

Writing of the islands in his diary he said: “The shallow, clear and still water of the lagoon, resting in its greater part of white sand, is, when illuminated by a vertical sun, of the most vivid green. This brilliant expanse, several miles in width, is on all sides divided by a line of snow-white breakers from the dark heaving waters, or from the blue vault of heaven by the strips of land crowned by the level tops of the cocoa-nut trees.”

The Tasmanian researchers are the same who discovered in 2017 that the remote Henderson Island in the South Pacific had the highest density of plastic debris anywhere on Earth.

Beach-back vegetation along the north-east side of Home Island  Credit: Silke Stuckenbrock

While the density of plastic debris on Darwin’s islands is lower than on Henderson Island, the total volume dwarfs the 38 million pieces weighing 17 tonnes found there.

Co-author Dr Annett Finger from Victoria University said: “The scale of the problem means cleaning up our oceans is currently not possible, and cleaning beaches once they are polluted with plastic is time consuming, costly, and needs to be regularly repeated as thousands of new pieces of plastic wash up each day.

“The only viable solution is to reduce plastic production and consumption while improving waste management to stop this material entering our oceans in the first place.”

The research was published in the journal Scientific Reports.