The Lesser Koa-Finch (Rhodacanthis flaviceps) is a species of finch in the Fringillidae family. One of the earliest of all the recorded lost species is the Lesser-Koa Finch. The Lesser Koa Finch has different coloring depending on gender and age. The only specimens caught was a family group with member of different ages and genders, perfect for studying. The males were gold yellow and were olive green on the bottom. The females were almost undistinguishable from its larger relative, other than the fact that it was darker in color. The juveniles are slightly mottled on the bellies and are similar to the females. It is small as its name proclaims, only five inches in size. It has its life centered around the Koa where it gets its nectar and fruit from. It is also the place the birds hid in small flocks to avoid people and the noon high sun. It was seen congregating with its lager relative, the Greater-Koa Finch. Several specimens were collected and sent to London, Cambridge, New York, Philadelphia, and Berlin. The bird appeared to be very low with its population until people brought cattle and created ranches in the Koa forests. This was fine at first but the younger Koa trees were being trampled under the heavy weight of the cow. The cows also stripped the leaves of the trees at a fast rate causing the trees to choke. The trees that were older were too tall to be defoliated but their roots were kicked and pulled out, causing them to grow weak and die. With the loss of the Koa trees the last birds began to die off until finally the bird was never seen again after the year 1891. It was also noticed that the birds were only seen once, and this was when the first and last specimen were shot. In all there were eight specimens that were collected. All of them from trees that were used by the Greater Koa Finch. There are several other species including one once from Oahu, one once from Maui and one living in Kona at the time. It has been confused as a House Finch and many novice bird watchers stake a false claim. It was also confused as the O'u, which was still common on Hawaii and Kauai. The Lesser Koa-Finch or Rhodacanthis flaviceps is listed on the IUCN Red list (1996) as Extinct.

Source

• BirdLife International 2004. Rhodacanthis flaviceps. 2006 IUCN Red List of Threatened Species. Downloaded on 10 July 2007.