Greater koa finch and maximum growth of a single species of koa finch. The greater koa finch was a granivore, preferring the pods and seeds of koa ("Acacia koa"). It was also observed eating caterpillars and aalii ("Dodonaea viscosa") seeds. The last confirmed sighting was in 1896, although there were sporadic later reports. Like its close relative the lesser koa finch, this bird lived in small stretches of mesic forest on the Big Island of Hawaii. These forests were dominated by its preferred food source, koa ("Acacia koa"), and were logged and replaced with pasture beginning in 1850. Grazing by cattle inhibited the
Koa wilt species of koa-finches, "Rhodacanthis palmeri" and "R. flaviceps", which fed on green koa seed pods. These species are now extinct due to habitat loss and avian malaria. It is important to preserve the remaining koa populations to helpt to avoid further native bird extinctions. Koa also has great cultural importance for native Hawaiians. The name “koa” means "brave, bold, fearless" or "warrior" in Hawaiian. Koa wood was used extensively in ancient Hawaiian society for constructing houses, spears, tools, canoe paddles, kahili (feathered standards of royalty), calabashes, ceremonies, and surfboards. Canoes were, and still are, carved from the trunks of koa