Greater koa finch below. It had a thick black bill which allowed it to break open seed pods that were found in the trees. In historical times, its range was largely confined to the Kona District of the island of Hawaii, although it was observed in the Kīlauea area in 1895. It was much more widespread prior to the arrival of humans in Hawaii, and related species lived on other islands. In Kona, it co-occurred with the closely related lesser koa finch ("Rhodocanthis flaviceps"), and the Kona grosbeak. The lesser and greater koa finches were once thought by scientists to be the minimum
Lesser koa finch was smaller than the other scientifically described koa finches, measuring on average only five inches in length. Its life cycle and feeding habits apparently centered around the koa plant from which it got nectar and fruit (and for which it was named). The koa also provided refuge for small flocks of the finch as it avoided people and the noon high sun. It was seen congregating with its larger relative, the greater koa-finch. Several specimens were collected and sent to London, Cambridge, New York, Philadelphia, and Berlin. The bird appeared to have always had a small population. When people brought