In November 2022, campground hosts on North West Island noticed something that could have become a major threat to one of the Great Barrier Reef’s important wildlife refuges: black rats had arrived.

The island, about 75 kilometres north-east of Gladstone, is part of Capricornia Cays National Park and supports important breeding populations of seabirds and nesting marine turtles.

Rangers quickly confirmed that the rats had spread across the island using remote cameras and Black Trakka ink monitoring stations.

The discovery came only three months after mice had been declared eradicated from North West Island, highlighting how quickly invasive pests can return.

Over the next 18 months, Queensland Parks and Wildlife Service (QPWS) and Gidarjil Land and Sea Rangers carried out an intensive eradication programme using aerial baiting, bait stations and traps.