In 2013, St Agnes and Gugh began removing invasive rats brought by 18th-century shipwrecks; 12 years later, Manx shearwater breeding sites rose from 22 to a record 225
In the latest 2025 monitoring data, St Agnes and Gugh recorded 225 apparently occupied breeding sites (AOBs) for Manx shearwaters In 2013, a major conservation effort began on St Agnes and Gugh in the Isles of Scilly to remove brown rats that had been harming nesting seabirds. According to the Isles of Scilly Wildlife Trust,…