Invasive Species Jeopardize Already Threatened Island Animals: Researchers have identified which of the approximately 465,000 islands worldwide are home to both highly threatened terrestrial vertebrates and invasive species that may endanger their survival. This distribution map could help conservationists decide how to prioritize prevention, control and eradication of invasive vertebrates, as well as serve as a baseline to document future changes to the status of highly threatened island animals. Global biodiversity loss is disproportionately rapid on islands, where invasive species are a major driver of extinctions. What's more, a recent review of international targets to prevent extinctions highlights the limited progress that governments and international bodies have made toward eliminating threats from invasive species. To address a global gap of information on the overlap between island biodiversity and invasive species, a necessary effort to pinpoint where conservation actions can prevent extinctions, Dena Spatz and colleagues created the Threatened Island Biodiversity Database. They found that 1,189 highly threatened vertebrate species breed on 1,288 islands, many of which are relatively small with minimal human habitation. Invasive vertebrates live on 779 of the islands with highly threatened vertebrates -- mammals are the most common invaders, living on 97% of these islands (with rats being one of the most widespread). For the less than one-fifth of islands with highly threatened vertebrates but no invasive vertebrates, biosecurity, or efforts to prevent invaders from becoming established, will be an important strategy. A diversity of conservation approaches and funding strategies are also required to effectively conserve native animals on islands with invasive species. Such interventions will likely also benefit less well-studied organisms such as plants and insects, the authors say.