‘You’ve got to remove every rat’: the race to protect Round Island

Invasive species on islands: when signs of the pests were discovered on the Scilly isle in January, a crack squad of conservationists mobilised to save threatened seabird colonies

Words and pictures by Alexander Turner

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As the boat weaves between the jagged rocks of the Scilly archipelago off the coast of Cornwall, Round Island, uninhabited but for a lonely Victorian lighthouse, comes into view. Those on board preparing for their visit are not armed with cameras and binoculars but with buckets of toxic cereal bait and rat traps.

When signs that rats were running riot over the island were first spotted in January 2022, a rescue operation to save resident seabirds kicked into action. There was just a small window of opportunity to attempt a total eradication" of the rats before Manx shearwaters and storm petrels returned in April.

The steep cliffs of Round Island as seen on approach