[3] Today, it is known to breed only on the Big Island, in stands of native ʻōhiʻa lehua (Metrosideros polymorpha) trees.

During breeding season one of the pair, possibly the female, has a distinctive yellow forecap area just above the upper mandible.

Common threats to the ʻio are illegal shootings, the degradation of their native forest habitat, poisoning, vehicle collisions, starvation, and predation from other animals.

Today it feeds largely on introduced animals such as rats, lizards, and game birds, as well as invertebrates such as insects.

The Hawaiian hawk was one of many birds unleashed in the third period of creation (wā) mentioned in the Kumulipo.