In the last half-century, disease-carrying mosquitoes helped wipe out several Hawaiian forest bird species. The ʻakikiki, on Kauai, is down to just a handful of individuals found in the wild.
Photo Credit: Leon Berard/2021
Federal wildlife officials aim to direct some $14 million from the new Bipartisan Infrastructure Law toward the urgent, ongoing effort to save 12 native Hawaiian forest bird species battered by avian malaria and headed toward extinction.
They’re also poised to finally put forth a proposed designated habitat for one of those imperiled birds, the iʻiwi, as required by law, according to the Department of Interior.
The new “Strategy for the Prevention of the Extinction of Hawaiian Birds,” which DOI released last week, would deploy by 2026 a sort of mosquito “birth control” program that aims to trim the number of disease-carrying insects that have invaded the birds’ forest habitats.
It would also expand captive breeding efforts at enclosures safely removed from the malaria. Such facilities already exist in the islands but they’ve reached full capacity, according to the DOI report. The strategy further calls for relocating birds by 2030 to new malaria-free forest habitats on Hawaii island.
Those approaches might not move quickly enough, however, to keep some of the most imperiled forest bird species from vanishing in the wild — as others already have. Warming temperatures linked to climate change have enabled the mosquitos to reach deeper and higher into their native habitats.
The DOI strategy acknowledges that four of Hawaii’s culturally and ecologically important honeycreepers – the ʻakekeʻe, the ʻakikiki, the ‘akohekohe and the kiwikiu – could go extinct in as little as one to two years. That’s well before the mosquito sterilization program would be fully deployed.
It’s also before the expanded captivity and relocation programs would fully come online, under the timeline laid out in the strategy. Still, local and federal officials say they hope the latter two approaches will help the honeycreepers in most danger hang on until the mosquito birth control program can be fully deployed.
“These efforts may be able to prevent extinction of some species until (the sterilization program) can provide mosquito-free habitat,” the strategy states.
Federal officials say they’ve approved a proposed critical habitat for the endangered i`iwi bird.
Jack Jeffrey Photography
Earl Campbell, a field supervisor with the U.S. Fish and Wildlife Service’s Pacific Islands Office, followed up in an email that “it is recognized that there is a risk of extinction for any of these (four) species within a one-to-10-year time frame.”
“Successful implementation of components of this plan could help save all or a subset of these four species,” he added.
Meanwhile, Fish and Wildlife, which falls under DOI, has separately approved its proposed critical habitat for the iʻiwi and submitted that to the Federal Register. The proposal could be made public as early as next week, according to Jordan Akiyama, a DOI spokesman.
Federal wildlife officials are already several years overdue in proposing that designated critical habitat, plus a recovery plan, for the iʻiwi, which is listed under the Endangered Species Act. They had agreed to finally get it done by this month under a court settlement reached last year with the Center for Biological Diversity.
Wolbachia To The Rescue?
In recent years, avian malaria-carrying “culex” mosquitos, which arrived on the islands from ships in the early 1800s, have decimated the populations of colorful Hawaiian honeycreepers whose distinctive songs used to echo across the forests.
Only 17 of more than 50 documented honeycreeper species that evolved in Hawaii remain, with avian malaria the main culprit for their rapid, continuing decline. Overall, Hawaii has been dubbed the “endangered species capital of the world.”
In 2015, for example, biologists recorded a population of about 70 ʻakikiki birds left in their native Kauai forests. In 2021, they found just five of the birds, according to the state’s Department of Land and Natural Resources.
This male kiwikiu was one of 13 endangered Maui parrotbills that were recently moved from one side of Haleakala to the other in 2019 in an effort to establish an “insurance population.” All but one of them died from disease-carrying mosquitoes.
Bret Nainoa Mossman/MFBRP
Workers with the state’s Division of Forestry and Wildlife have been collecting mosquito samples in forest areas of Kauai, Maui and the Big Island in recent months.Their goal, as state officials explain, is to gauge the best places to eventually release male mosquitos exposed to the naturally occurring bacteria Wolbachia.
Wolbachia is often used to prevent the spread of malaria to protect public health, but in terms of endangered species protection it’s a novel approach, officials say.
Eggs from the female mosquitos that mate with those males introduced into the bird habitats will never hatch, and wildlife officials say that should suppress the population of insects carrying avian malaria.
The Wolbachia-infected males will have to be released into the habitat at regular intervals in order for the honeycreeper populations to recover, they add.
Maui’s imperiled kiwikiu bird might be able to stave off extinction if the next several years see cooler temperatures, buying time for the mosquito sterilization program to flourish in their habitat, according to Hanna Mounce, coordinator of the Maui Forest Bird Recovery Project.
“The forest birds of Hawaii are unique, not only because of their evolutionary history but their cultural significance to the Native Hawaiian people,” Campbell said in a DOI release. “We must continue working with our conservation partners as we strive to preserve our forest birds for future generations.”
Civil Beat’s coverage of climate change is supported by the Environmental Funders Group of the Hawaii Community Foundation, Marisla Fund of the Hawaii Community Foundation and the Frost Family Foundation.
Source: Honolulu Civil Beat