St Helena has long been known for its high proportion of <answer>endemic</answer> birds and vascular plants. The highland areas contain most of the 400 <answer>endemic</answer> species recognised to date. Much of the island has been identified by BirdLife International as being important for bird conservation, especially the <answer>endemic</answer> Saint Helena plover or wirebird, and for seabirds breeding on the offshore islets and stacks, in the north-east and the south-west Important Bird Areas. On the basis of these <answer>endemic</answer>s and an exceptional range of habitats, Saint Helena is on the United Kingdom's tentative list for future UNESCO World Heritage Sites.
Saint Helena has a high proportion of what kind of birds?
endemic