To the few humans who hear it, the song of the kiwikiu, or Maui parrotbill, tells a story of survival and recovery. Most endemic Hawaiian forest birds are threatened by invasive species, habitat destruction and mosquito-borne disease, but few more so than the kiwikiu: There are only about five hundred of the little yellow birds left, making them the most critically endangered forest bird on Maui. Named for their parrot-like bills, all of them live in the Waikamoi Preserve above 4,500 feet on the eastern slope of Haleakalā. The wet ‘ōhi‘a forest there, however, is marginal habitat: Fossil evidence suggests that kiwikiu prefer drier, lower-elevation koa forest like that once found on the leeward side of the volcano.
“These birds are confined to about fifty square kilometers of really wet rainforest,” says Hanna Mounce, coordinator for the Maui Forest Bird Recovery Program, which has focused on saving kiwikiu since 2006. “They are there because that is the only pristine forest left on Maui—but it is really hard to be a twenty-gram bird living in an area that gets three hundred inches of rain.” More than that, the kiwikiu’s low density in this marginal habitat means that releasing more birds won’t by itself help the situation.“We really can’t produce more kiwikiu within the forest we have,” says Mounce. So if the solution isn’t necessarily more birds, it’s more—and more suitable—forest.
The MFBRP, with support from the University of Hawai‘i and other partners, set about creating that forest in 2012, and they’ve made steady progress. To date they’ve planted more than thirty thousand native plants in a 420-acre fenced area of the Nakula Natural Area Reserve on leeward Haleakalā, with plans for planting ten thousand more this year. In January 2018 they will introduce the first group of kiwikiu from captive birds maintained by San Diego Zoo Global in facilities on Maui and Hawai‘i Island. In the future the project will also relocate wild birds.
It took almost two hundred years for the Maui parrotbill’s forest to disappear, and restoring that habitat won’t happen overnight. “It might take twenty-five years to have a really beautiful koa forest,” says Mounce, “but we still have to start now.”