The Po'ouli was the Hawaiian honeycreeper known as the black-faced honeycreeper that disappeared in 2004. Its scientific name is Melamprosops phaeosoma, and it was endemic to the wetter eastern slopes of Maui.
The bird had a distinctive black mask across its face, brown upperparts, and pale gray underparts. It was first discovered in 1973, making it the first Hawaiian honeycreeper species found since 1923. Its diet included native tree snails, insects, and spiders, and it nested in forests containing ʻōhiʻa lehua.
By 1997, only three individuals were known. Conservationists attempted to capture birds for captive breeding, including a 2004 effort; a male was captured in September but died in November before a mate could be found. No Po'ouli has been confirmed since then. The species was formally classified as extinct by the IUCN in 2019, so “went extinct in 2004” refers to the last known birds and confirmed records, not the later administrative declaration. Mākihi, ʻApapane, and ʻIʻiwi are different Hawaiian birds.