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EXTINCT

Oahu Koa Finch

Rhodacanthis sp.
The Lesser Koa Finch was also called the Yellow-headed Koa-finch.Only a few specimens were ever collected.The species was so rare that it at first was thought to be a hybrid.The Lesser Koa finch formed mixed flocks with the Greater Koa-finches.

By the nineteenth century the Lesser Koa-finch and Greater Koa -finch were restricted to the upland Koa forests on the leeward slopes of Mauna Loa, on the island of Hawaii.Fossils indicate that they were once widespread in the lowlands of that island.

The tragic end of the Lesser Koa-finch was recorded by the collectors who shot the last remaining bird. The following is from "Birds of Hawaii" by George Munro. "September 30, 1891. Palmer killed another (Koa-finch) a much smaller bird with golden head and neck and light yellow breast .".

Oahu Population Data
Storrs L.Olson and Helen F. James recovered bird bones from the sinkholes at Barbers Point and Ulupau Head on Oahu from a possible new species. In 1991 they wrote, "We have recorded fossils of Rhodacanthis from Oahu.These differ from R. palmeri and R. flaviceps, but not in ways that we consider important enough to justify formally describing new species at this time, considering that our comparative material is limited to only one partial skeleton of each species. They went on to write," These Oahu fossil specimens are similar in size to R. flaviceps but differ in having a larger narial opening, a deeper medial trough on the ventral surface of the maxilla,and a decurved rather than straight anterior portion of the tomial crest of the mandible.In the last two characters, the fossils agree more with the larger R.palmeri than with R.flaviceps.Faced with such an ambiguous combination of characters, we are unable to suggest whether this form is a distinct species,is conspecific with R.flaviceps, or is conspecific with R. palmeri



Please do what you can to save the native Hawaiian forest bird species that remain.

Aloha,
Michael Walther