Henderson Island

Henderson Island is a raised coral atoll in the South Pacific, one of the most isolated pieces of land in the world and the largest of the four islands that make up the Pitcairn Islands territory. It has been uninhabited by Europeans but shows evidence of Polynesian settlement dating to the 12th century, and was continuously inhabited by Polynesians until the early 15th century before being abandoned. The island covers approximately 37 square kilometres and rises to about 33 metres above sea level at its highest point, with steep limestone cliffs on three sides and a narrow beach on the north-western shore where landings are possible in calm conditions.

The island was inscribed on the UNESCO World Heritage List in 1988 in recognition of its extraordinary biodiversity and the fact that it has remained largely free from introduced species and human disturbance. Henderson is one of the few raised coral atolls in the world that has not been significantly altered by humans, and it supports a range of endemic plant and bird species found nowhere else on earth, including the Henderson petrel and the Henderson island crake. The interior of the island is dense with forest and scrub that has never been cleared or planted, creating a genuinely primeval island landscape.

The beach on the north-western shore is one of the most striking features of the island, consisting of white coral sand that contrasts sharply with the dark volcanic rock of the surrounding cliffs. The beach is also the main site where plastic flotsam from passing ships accumulates in large quantities, a reminder that even the most remote places on earth are connected to global shipping routes and oceanic pollution. The approach by sea is difficult and landing is only possible in calm weather; the island has no permanent inhabitants and no built infrastructure.

The scientific significance of Henderson Island extends well beyond its status as a bird sanctuary. The island's isolation has resulted in an evolutionary environment that has produced numerous endemic species of plants and invertebrates found nowhere else on earth. The Henderson islandsnail and several endemic insect species are confined to the island's leaf litter and forest floor, their survival entirely dependent on the continuation of the island's undisturbed forest ecosystem. The coral reefs surrounding the island also support a distinct marine fauna, though comprehensive surveys have been limited by the difficulty of conducting fieldwork in such a remote location.

The plastic pollution problem on Henderson's north-western beach has attracted international scientific attention as an indicator of the global reach of oceanic plastic contamination. Studies conducted on the island have documented thousands of individual plastic items washing ashore each year, accumulating in the wrack line above the high-tide mark. The items include consumer packaging, fishing gear and microplastic fragments, representing a cross-section of global plastic production that has travelled thousands of kilometres through the ocean gyre system to arrive at one of the world's most remote shorelines.

UNESCO World Heritage designation in 1988 reflects its status as one of the world's most significant undisturbed island ecosystems.

It supports multiple endemic species found nowhere else, including the Henderson petrel and the Henderson island crake.

The island represents a near-pristine raised coral atoll, a habitat type that has been heavily degraded across most of its global range.