Maui's Forest Birds: Six Honeycreepers, a Mosquito, and a Race Against Extinction

A crisis on Maui

Maui is famous for its beaches, its Hawaiian culture and its wildlife — and it is close to losing one of its treasures: native forest birds found nowhere else on Earth.

People brought changes these birds had never faced in their evolution, all in a short time. The worst is non-native mosquitoes, which spread disease — above all avian malaria, which is deadly to honeycreepers. It has driven steep declines and threatens many species with extinction. But a way to turn the tide is within reach.

• More than 50 species of honeycreepers once lived in the Hawaiian Islands; only 17 remain.
• Three species have gone extinct on Maui alone in the past 35 years, and many more across the state are close behind.
• Maui and Haleakalā National Park are home to six of the remaining native forest bird species. They matter to the forest and to Hawaiian culture alike.

Meet the birds

ʻApapane. NPS photo.

ʻApapane (Himatione sanguinea) — not threatened; found only in Hawaiʻi.

• Iridescent red, with a short black bill and black legs that set it apart from the other red native bird, the ʻiʻiwi.
• Works the ʻōhiʻa lehua blossoms for nectar, a few seconds per flower, always moving.
• Its songs are long runs of mechanical chattering.

ʻIʻiwi. NPS photo.

ʻIʻiwi (Drepanis coccinea) — threatened, vulnerable; found only in Hawaiʻi.

• Red, with black-and-white wings and a long, slender orange bill.
• Takes nectar from many kinds of flowers.
• Creaks, gurgles and whistles that sound like a rusty hinge.
• Hosmer Grove is one of the best places to see one, especially when the yellow-flowered māmane shrubs bloom.

Hawaiʻi ʻamakihi. NPS photo.

Hawaiʻi ʻamakihi (Chlorodrepanis virens) — not threatened; found only in Hawaiʻi.

• Yellowish green, with a short, slightly down-curved bill; females and young are grayer and browner.
• Eats nectar and insects.
• Known for sneezy, whiny calls — it sometimes seems to scold passing birdwatchers.

Maui ʻalauahio. NPS photo.

Maui ʻalauahio (Paroreomyza montana) — not threatened but declining; found only on Maui.

• Small and bright yellow; young birds are gray. Its straight pink bill tells it apart from the greener, down-curve-billed ʻamakihi.
• Eats insects, and is rarely alone: family groups travel together, "chipping" to each other.
• Its song is a repeated whistled phrase: "whichy-wheesee-whurdy-whew."
• Often seen at Hosmer Grove and Palikū Cabin.

Kiwikiu. NPS photo.

Kiwikiu, or Maui parrotbill (Pseudonestor xanthophrys) — endangered; found only on Maui. Fewer than 200 remain.

• Stocky, olive green above and yellow below, with a big hooked bill it uses to split branches for insects in high wet forest.
• So few are left that it is very rarely seen outside dense native forest away from public view — very unlikely even at Hosmer Grove.
• Calls a short "chip," like the ʻalauahio, or whistles like the ʻiʻiwi; its song repeats whistled "cheery" notes, often falling in pitch.
• Its original Hawaiian name was lost. In 2010 the Hawaiian Lexicon Committee named it kiwikiu: kiwi for its curved beak, kiu for its secretive ways.

ʻĀkohekohe. NPS photo.

ʻĀkohekohe, or crested honeycreeper (Palmeria dolei) — endangered; found only on Maui. Fewer than 2,000 remain.

• One of the largest honeycreepers: mostly black, with body feathers tipped orange-red and throat and breast feathers tipped silvery white.
• Mostly drinks nectar, but also eats insects and spiders.
• Clucks, gurgles, raspy croaks and buzzes — rather like a frog.
• Once on Molokaʻi too, like the kiwikiu; now only in a narrow strip of high native forest on Haleakalā. Hard to see, since it keeps to intact forest; at Hosmer Grove, young ʻapapane are sometimes mistaken for it.

Why they're disappearing

The causes fall into three groups: introduced species, habitat destruction and climate change.

• Mosquitoes arrived in 1826. Hawaiʻi had none of any kind until a whaling ship brought the southern house mosquito to Lahaina.
• Avian malaria followed soon after, and has driven many native forest birds extinct. One bite from an infected mosquito can kill a forest bird.
• Warming lets the mosquito spread to higher elevations, invading more and more of the birds' last habitat.

Without help, these birds could be lost for good.

Drawing Connections: Haleakalā National Park — a Park Service film told in watercolor paintings, which the park links on the forces behind the birds' decline (3 minutes, 44 seconds). National Park Service.

Hope: a mosquito that can't reproduce

Saving them will take fast action and major conservation work. Haleakalā National Park is working with the State of Hawaiʻi and other agencies to do it.

How Wolbachia stops mosquitoes breeding. NPS graphic.

• Wolbachia is a naturally occurring bacterium that lives only inside the cells of insects — including Maui's southern house mosquitoes — and some other arthropods.
• Scientists found that mosquitoes carrying different strains of Wolbachia can't reproduce together.
• The Incompatible Insect Technique (IIT) puts that to work: raise male mosquitoes (males don't bite) in a lab with one strain, and release them where wild mosquitoes carry another. When a wild female mates with one, the strains don't match, and none of her eggs hatch.
• The result of this safe, targeted method: the mosquito population crashes, and the forest birds get a fighting chance.

Sources

Based on "Time Is Running Out: Maui's Forest Birds Will Go Extinct without Action," Haleakalā National Park, National Park Service; a work of the United States government in the public domain. The film is the Park Service's own, linked from the source page.