Ōkai and ‘Aiea

The Hawaiian word for moth is ōkai. If you see it flapping in the night, you might mistake the giant Blackburn’s Sphinx Moth (Manduca blackburni) for a bat or small bird. This large endemic moth, ōkai in Hawaiian, has a 5 inch (13 cm) wingspan. They were once part of an extensive dry forest ecosystem. The Blackburn’s sphinx moth feeds on and pollinates a wide variety of plants, including the koali‘awa, maiapilo, and ‘ilie‘e.

The Blackburn’s sphinx moth has a relatively short life cycle. It may only take 56 days for an egg to mature into an adult, in ideal conditions. If it is too hot or dry, the pupae can wait underground for up to a year before emerging.

The adult female lays its eggs on plants in the nightshade family. The ‘aiea tree (Nothocestrum latifolium) is the favorite nursery for larvae of this moth. Introduced nightshades where Blackburn’s sphinx moth caterpillars have also been found are tree tobacco, eggplant, and tomato.

The Blackburn’s sphinx moth used to be widespread on all main Hawaiian islands. It was thought to be extinct by the 1970s, along with the loss of most of the lowland dry forests. In 1984, a small population was found in east Maui, living near a grove of ‘aiea trees where its caterpillars feed.

Efforts are being made to restore lost habitat with both the ‘aiea trees, and the flowers that the adult moth feeds on. Other factors, such as predatory ants and parasitic wasps, are obstacles to hurdle in an effort to restore the population of the Blackburn’s sphinx moth.