75 Tonnes of Poison Couldn't Save Henderson Island: Rats Bounced Back in 2 Years

In 2011, conservationists launched a major rat eradication effort on Henderson Island, a remote South Pacific location, deploying around 75 tonnes of poisoned bait. Despite the scale of the operation, only 60 to 80 rats managed to survive the campaign. Within two years, the surviving population had rebounded to its previous levels. The failed effort highlights how difficult it is to fully eliminate invasive species, even with intensive intervention. The case of Henderson Island serves as a stark reminder of the resilience invasive rodents can display against eradication attempts.