WatchList Species Account for ‘O’u (Psittirostra psittacea)

Qualifies for the list as a Red List Species

The ‘O’u, when last observed, was restricted to remote, high-elevation native forest; most sightings in the last 50 years have been above 1,200 m. Common before 1900, this species has not been found on Kauai since 1989 nor on the island of Hawaii since 1987, despite forest bird surveys by the State Department of Land and Natural Resources, the National Park Service, and the National Bilogical Survey. Recent reports of the bird have not been confirmed. Formerly it was also known from Oahu, Molokai, Maui, and Lanai.

Its thick bill, strongly hooked at the top, was adapted for feeding on its principal food, the fruits of the ‘ie ‘ie vine; it also feeds on a variety of native and introduced fruits, but also on nectar and invertebrates. Among the causes for the decline of the species are a lava flow, which passed through a stronghold for the bird on Hawaii, and hurricanes, which have struck Kaui twice in the last generation.

Logging and agriculture destroyed much of the native forest it preferred, and feral pigs have degraded its habitat and facilitated the spread of mosquitoes, the vectors of diseases implicated in the rapid decline of the ‘O’u. In addition competition for food with introduced birds and rats may have depressed the populations. Further searches for the bird should be carried out, as there is a chance that a remnant population may still exist. Removal of feral pigs, planting of native vegetation, and a captive breeding program are all necessary steps to be taken if any of the birds are rediscovered. The species is federally listed as endangered and classified as critical by BirdLife International. However as is the case with so many of the native passerines of Hawaii, at present it probably exists only in museum specimen trays.