The Weka (Gallirallus australis) is a species of flightless rail endemic to New Zealand. The species is divided into four subspecies: the Buff Weka (Gallirallus australis hectori), the Western Weka (Gallirallus australis australis), the North Island Weka (Gallirallus australis greyi), and the Stewart Island Weka (Gallirallus australis scotti - shown). The Weka is thought to have diverged from a flying ancestral species that had dispersed to New Zealand from modern day Australia. Weka populations have come under pressure from invasive predators/competitors in addition to pressures from habitat loss/conversion since the arrival of humans onto New Zealand. Many modern conservation efforts have been aimed at restoring Weka populations through introducing the species onto offshore-island reserves. While these conservation efforts have been successful, Weka have been known to occasionally become a pest on the islands where they are introduced.