In a bid to save native bird species from going extinct, the National Park Service at Haleakalā National Park in Hawaii wants to upend the reproduction of mosquitoes that carry avian malaria that is deadly to the birds.

The approach involves releasing male Culex mosquitoes that carry a naturally occurring bacteria, Wolbachia, that differs from the Wolbachia strain females carry. "The bacteria has kind of hijacked the reproductive system of the mosquitoes," Chris Warren, the park's forest bird program manager, told the Traveler earlier this year. "If one mosquito that has a type one Wolbachia tries to breed with another mosquito that has a different type, Wolbachia type two, none of those offspring survive. They lay eggs, but the embryos die."

The Hawaiian islands once counted more than 50 species of endemic forest birds, but today there are fewer than 17 species, according to the National Park Service, some with fewer than 500 individuals left.

An adult Maui parrotbill/Alan Liberman, Keauhou Bird Conservation Center via USFWS

The kiwikiu, a variety of honeycreeper also known as the Maui Parrotbill, is one of the dwindling species and is predicted to vanish from the Earth in just six years. Once abundant across Maui and Moloka'i, today fewer than 200 individuals are believed to be found across less than 8,000 acres on Maui in Haleakalā National Park, Hanawi Natural Area Reserve, and The Nature Conservancy’s Waikamoi Preserve.

The kiwikiu's decline has been driven by loss of habitat to the encroaching human footprint, natural predators, and even feral cats. Today, though, the invasive Culex mosquito poses perhaps the greatest threat, for these insects can not only reach the kiwikiu in the highest koa branches, but they are moving higher and higher in the mountains on the island, following this honeycreeper species. And when bugs poke the birds for a quick meal, they can leave behind a deadly dose of avian malaria.

"Most of Hawaii's honeycreepers, which is, and was, the most diverse group of native birds, they're immunologically naive to avian malaria, which is a really common disease throughout the world," said Warren. While many bird species simply get sick and then recover from avian malaria, he said, the kiwikiu and other native Hawaiian bird species "simply drop dead." 

The park is working on an environmental assessment on the project and is seeking public comment on the proposal, which is being prepared in cooperation with the Hawaii Department of Land and Natural Resources. 

Two virtual meetings are scheduled for early January:

Tuesday, January 3, 2023 at 5:30-7 pm HST meeting link: https://tinyurl.com/2p2p22b5  

Thursday, January 5, 2023 at 5:30-7 pm HST meeting link: https://tinyurl.com/nhfewvb7   

More information on the project can be found on the Park Service's Planning, Environment, and Public Comment website. To submit a comment on the project, click the “Open For Comment” link on the website. 

Public comments are being accepted through Jarnuy 23, 2023.