Invasive species in Hawaii and health-related problems. The introduction of mosquitoes to Hawaii has resulted in the spread of avian malaria, and increases the risk of dengue and west Nile virus (not known to be in Hawaii yet). Other native species can be affected by invasive species diseases as well, such as the once-dominant koa tree being killed by koa wilt, which is believed to have been brought into Hawaii on an ornamental acacia plant, and the 'ohi'a tree, now being affected by Rapid Ohia Death. Invasive predators can severely reduce the population sizes of native species, or even drive them extinct, because native
Koa people their territory. In 1998 grazier Noel Kennedy applied to the Federal Court to have his property Castle Hill declared to be free of native title. This was challenged by the descendants of the Koa the following year, in a counterclaim for native title to the Castle Hill Pastoral Holding and the Bladensburg National Park in the Shire of Winton. In mid-2002 a Federal Court declared that the Koa claim did not apply to Kennedy's pastoral lands because the Koa could not demonstrate continuity of cultural practices in that area over the last half-century. In 2015, a further claim to title