Nohoanu and ‘I‘iwi

Nohoanu (Geranium arboreum) is an endangered endemic Hawaiian geranium. It was once common on the lower slopes of Haleakalā, Maui. The nohoanu co-evolved with native birds to become the only geranium adapted to bird pollination. The curved flower is shaped to match the beaks of honeycreeper birds feed on its nectar. Each species of bird and plant has dedicated to each other. The pairing of birds with plants reduces competition between bird and plant species.

The habitat of the wild nohoanu has been reduced to a few scattered patches. Most of the former habitat has been taken over by pastures for cattle. The loss of the nohoanu is also a loss for the ‘i‘iwi (Vestiaria coccinea), scarlet honeycreeper bird. The curved beak of the ‘i‘iwi is perfectly adapted to the nohoanu flower. If the ‘i‘iwi goes extinct, so will the nohoanu.

The ‘i‘iwi used to be on all major Hawaiian islands. Today they are mostly only in the native forests of Kaua‘i, Maui, and Hawai‘i. Only a few dozen remain on O‘ahu and Molokai. Diseases like avian malaria, avian pox, and competition from introduced birds like the mejiro threaten the ‘i‘iwi.