In 2025, helicopters flew grid patterns back and forth across this island, dropping bait in the largest aerial rodent eradication ever attempted in South Australia. Specialists flown in from New Zealand and Tasmania hunted down every last feral cat. By the time they finished, the three remaining invasive mammals, cats, rats, and mice, were gone, following the earlier removal of cattle and sheep as the farming operation wound down, and Flinders Island had begun an extraordinary transformation: from a worn-out farm into a refuge for the very creatures Australia is fast losing everywhere else. It is the most ambitious wildlife reset the state has ever tried, on a windswept lump of land 32 kilometres off the coast.
On 13 February 1802, Matthew Flinders sailed the Investigator through the islands off Eyre Peninsula and named this one after his younger brother Samuel, the sloop's second lieutenant. His crew rowed ashore and took notes. They found the lower ground thick with large bushes, a small kangaroo-like macropod they described as numerous, and beaches crowded with Australian sea lions, whose family groups they inspected at close range. Firewood, they grumbled, was scarce, just a few stunted casuarinas. It was a snapshot of an island still entirely wild, taken in the last days before everything about it changed.
The wildness did not last. By the 1820s a sealing camp had been set up on the island's southeast side, and a whaling station followed, part of the brutal extractive industries that swept this coast. Then came the farmers. Sometime before 1911, the Schlink family is thought to have introduced sheep, horses, cattle, and crops; by then much of the island had been cleared and was yielding up to two thousand bags of wheat a year. The toll on native life was staggering. By the time the island sold in 1911, an estimated 30,000 wallabies had been killed on it. From the late 1970s the Woolford family ran it as a merino sheep station, and they hold it still.
A 1934 account described little penguins on the island "waddling soldier-like among the rocks and cave entrances that constitute their homes." Decades of introduced predators have nearly silenced that scene. By 2006 the colony was thought to be probably declining, fewer than twenty birds, clinging on at the base of cliffs that feral cats could not easily reach. The island remains part of the Investigator Islands Important Bird Area, vital for breeding short-tailed shearwaters, white-faced storm-petrels, and the biome-restricted rock parrot. Removing the cats alone would not have saved the birds; ecologists warned that with the cats gone, the rats would explode, so both had to go together.
The turning point came in 2020, when the Woolfords signed a conservation agreement with the South Australian government covering most of the island, an unusual partnership between a private family and the state. The Flinders Island Safe Haven Project followed, backed by federal and state funding, with the goal of erasing the invasive animals entirely. The 2025 campaign achieved exactly that. Now the island enters a waiting period: not until roughly mid-2027, after a minimum two-year pest-free stretch, can it be officially declared clean. Only then begins the project's true purpose, reintroducing threatened native mammals to a land they once shared with the sea lions.
There is one more secret beneath the grass. Geologists have found a wide range of kimberlite indicator minerals on Flinders Island, the telltale traces that can point toward diamonds, and exploration has continued in search of them. It is a strange double identity for one small island: a place being painstakingly returned to its pre-settlement wildlife on the surface, while deep below, the same ground hints at the kind of mineral wealth that has transformed remote landscapes the world over. For now, the wildlife is winning.
Flinders Island lies at 33.72 degrees south, 134.48 degrees east, in the Investigator Group off the western coast of Eyre Peninsula, South Australia, roughly 32 km west of the mainland town of Elliston. At nearly 4,000 hectares it is the fourth-largest island in the state and reads clearly from the air, with Point Malcolm as its most northerly headland and the rugged Topgallant Islands about 3.5 nautical miles to its east. The nearest mainland airfield is Elliston Airport (ICAO YELL); Port Lincoln Airport (YPLC) lies to the southeast and Ceduna Airport (YCDU) to the north. A viewing altitude of 3,000 to 6,000 feet captures the whole island, its cliff-lined coast, and the surrounding Investigator Marine Park waters. The island has a private airstrip used by its owners. Southern Ocean swells and afternoon sea breezes are typical along this exposed coast.