Island bugs boom after rat invasion ended

The natural environment of Lord Howe Island, a World Heritage-listed site 600km off Australia's east coast, is witnessing an extraordinary revival of its invertebrate life. A significant campaign initiated seven years ago to eliminate approximately 300,000 invasive rats and mice has resulted in a remarkable 60% increase in the total number of invertebrates, according to a recent study in Biological Invasions. This surge follows decades of ecological damage caused by rodents, which arrived on the island in the mid-19th century and decimated native flora and fauna, pushing numerous species, including at least 13 invertebrates, to extinction.

Scientists meticulously documented the island's insect populations before the 2019 eradication program, enabling a clear measurement of the post-eradication recovery. Researchers collected over 24,000 invertebrate specimens, revealing a thriving ecosystem that feels 'otherworldly.' The removal of rodents, which indiscriminately consumed most life forms, has allowed native species like birds and reptiles to flourish. This ecological reorganization is expected to benefit the entire island, with predictions of increased bird and gecko populations and improved plant and soil health. The rediscovery of a weevil species thought extinct for over a century underscores the profound recovery underway.