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

Qualifies for the list as a Red List Species

 

Abert's Towhee

© H. Douglas Pratt, Birds of Hawaii. Reprinted by permission of Princeton University Press.

The ‘O’u, when last observed, was restricted to remote, high-elevation native forest; most sightings in the last 50 years have been above 3,900 feet. 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 Biological Survey. The 'O'u was also known from Oahu, Molokai, Maui, and Lanai. Recent reports of the bird have not been confirmed.

 

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 fed on a variety of native and introduced fruits, 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 the 'O'u preferred, and feral pigs have degraded habitat and facilitated the spread of mosquitoes, the vectors of diseases implicated in the rapid decline of many native Hawai'ian birds. Competition for food with introduced birds and rats may also have depressed this bird's populations.

 

Further searches for the 'O'u 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, like so many of the native passerines of Hawaii, at present the 'O'u probably exists only in museum specimen trays.