O'ahu Forest National Wildlife Refuge is located on the upper slopes of the misty northern Ko'olau Mountains, and protects some of the last remaining intact native forests on O'ahu. Many of the native plants and animals that once thrived in these forests are either extinct or on the brink of extinction. Management intervention is needed to stabilize native ecosystems and prevent more species from becoming extinct. The O'ahu Forest Refuge supports at least 17 species of endangered plants, 4 species of endangered tree snails, and 1 species of endangered bird, along with other rare native flora and fauna. At least nine native natural communities have been identified in the area, including lowland mesic forest types, rainforest communities, high-elevation cloud forest, and freshwater streams.