Since 1997, the Oahu Army Natural Resource Program has been controlling rats using diphacinone rodenticide in small-scale bait station grids in combination with rat traps for the protection of one endangered forest bird species, 5 species of endangered Oahu tree snails, and 9 species of endangered plants in 2 mountain ranges on the island of Oahu. Endangered tree snail and some plant populations are protected year-round. Other plants are only ...