Oʻahu nukupuʻu bill to pluck insects found underneath tree bark, the Oahu nukupuu fed on insects on flowering trees such as the koa ("Acacia koa") and ohia ("Metrosideros polymorpha"). These trees attract a large amount of insects due to their nectar-filled flowers. The Oahu nukupuu fed on koa in high elevation forests and fed on ohia in low elevations. The species was believed to have vanished as the spread of disease occurred, killing off nukupuu populations across the islands. In order to control the rat population in the sugar cane fields, mongooses were introduced to Hawaii and were suspected to be predators
KOA (AM) heard on KOA include Bob Martin, Don Zimmer, Gus Mircos, Alex Stone, and Steffan Tubbs, Rollye James and George Weber. The late Rick Barber was heard for 30 years on KOA. Consumer advocate Tom Martino and former FEMA official Michael D. Brown were KOA hosts until they switched to sister station KHOW. Radio host Alan Berg broadcast his talk show from the station, but was shot and killed by members of the white supremacist group The Order on June 18, 1984. Another host from an earlier era was Leigh Kamman, who hosted jazz programs during World War II. Kamman returned