Kaharoa and the adjoining Onaia Ecological Area are renowned for kokako, once common in lowland forest but now endangered. Their numbers have fallen dramatically since European colonisation. Fewer than 1400 survive in the North Island.The kokako may be our most beautiful songbird, using a variety of sounds including clicks, buzzes and mews, especially around dawn. At other times you may see one high in the tree canopy.
In recent years the Kaharoa Kokako Trust, DOC, Environment Bay of Plenty and volunteers have improved the forest health and the numbers of kokako in the area has increased. There are also good populations of tui, bellbirds, whiteheads, robins, morepork owls, native pigeons and even a few North Island brown kiwi. An impressive range of native trees include rimu, totara, kohekohe, tawa, puriri, rewarewa, mahoe, kamahi, nikau and mamaku. Deep gorges shelter the rare kingfern (para).