Ward Island does not look like much, and that is precisely the point – what you see is the eroded stub of something far older and grander. At its heart is a volcanic plug, granite that crystallised from molten rock more than fifteen hundred million years ago, when this corner of the planet was still being assembled. The summit was later buried under sand that hardened into limestone, then patiently ground back down by the sea over a span of time the mind cannot really hold. The island itself, in its present form, is young by comparison: it was drowned into being only about nine and a half thousand years ago, when rising seas at the end of the last ice age flooded the low surrounding country and left these few high points stranded as islands. Deep time made the rock; recent time made the island.

Nothing grows tall here. A 1980 survey found just twelve species of plant clinging on, all of them low, all of them shaped by salt and relentless wind into a flattened heath that hugs the rock. Marsh saltbush fills the deepest pockets of sandy soil; nitre bush takes the limey ground; pointed twinleaf colonises the orange, decomposing sandstone. It is a hard, sculpted, miniature landscape – the kind of vegetation that survives by refusing to reach for the sky. Among it nest seabirds in their thousands: short-tailed shearwaters, white-faced storm-petrels, ospreys and white-bellied sea-eagles riding the updrafts off the cliffs, sooty oystercatchers picking the tideline.

The name Ward sits inside a larger one. On that same February day in 1802, Flinders gathered this scatter of islands – Flinders Island, the Pearson Isles, the Topgallant Isles, the Waldegrave Islands and the Ward Islands – under a single banner and called them the Investigator Group, after his ship. He was in the middle of one of the great feats of maritime surveying, charting the unknown southern coast of Australia with a precision that would stand for generations, often working from a heaving deck within sight of rocks like these. To him the Ward Islands were a minor entry in a vast ledger of capes and bays and shoals. But the act of naming them tethered this anonymous granite to a specific moment in history, and to a specific man far from home, marking the chart with his mother and his mission in the same stroke.

Ward Island matters most for what it shelters. A small colony of Australian sea lions – one of the rarest seals in the world, and the only one found nowhere but Australian waters – breeds on these shores, hauling out alongside New Zealand fur seals on rocks the swell rarely leaves dry. Their presence is why the place is guarded. The islands first became a fauna reserve in the 1960s, joined the Investigator Group Conservation Park in 1972, and in 2011 were lifted into the stricter Investigator Group Wilderness Protection Area, the surrounding water added to a marine park the following year. The protection that matters most, though, is also the simplest and the oldest: sheer distance, a long reach of cold and dangerous sea that keeps the world at arm's length and the sea lions, for now, undisturbed.