Vicia menziesii Spreng., Hawai'i's first officially listed endangered plant species, formerly occurred across a large area in the upper montane-mesic forest habitat on the windward side of the island of Hawai'i. Until this species was `rediscovered? in 1974, it had last been seen in 1915, and it was presumed to be extinct. The population is presently thought to number 150?300 plants, most of which are seedlings. These are located within a 200 ha area on the eastern flank of Mauna Loa volcano. The primary factors responsible for the decline of V. menziesii are habitat loss and excessive predation on the plants by introduced ungulates. Continued logging and cattle grazing within its remnant range are major threats to its existence. Enhancing the survival of V. menziesii may best be accomplished by stabilizing its remaining habitat and allowing the population to reestablish itself naturally.