LIHUE — Forest bird conservationists on Kaua‘i are now combating both invasive species and growing pessimism, as environmentalists fear this field season may mark the last time they see ‘akikiki in the wild.
Found only on Kaua‘i, the ‘akikiki is one of several critically endangered forest bird species on the island. Even then, the bird’s situation is particularly dire — a University of Hawai‘i report estimated that only 45 ‘akikiki existed in the wild as of 2021, and anticipated the bird would most likely face extinction sometime this year.
“This is one of the last places where we’re still seeing a ton of native forest birds, where everywhere else, just in the last couple of years, they’ve quickly and suddenly vanished,” said Justin Hite, Kaua‘i Forest Bird Recovery Project (KFBRP) field supervisor, while on a field expedition atop the Alaka‘i Plateau. “And we think it’s because of mosquitoes.”
Once found across the island, the ‘akikiki has since lost nearly all of its habitat to invasive southern house mosquitoes carrying avian malaria. Possessing little to no immunity against the disease, the birds are now only found within a patch of the Alaka‘i Wilderness Preserve no larger than 14 square miles, as the mosquitoes can’t withstand the colder temperatures at higher elevations.
But as climate change increases air temperatures, mosquitoes have successfully crept into much of what little safe habitat is left, further ravaging the birds’ already dwindling numbers.
In an effort to protect the ‘akikiki and other forest birds from this growing threat, the Department of the Interior announced in December 2022 a multiagency, multimillion-dollar strategy involving captive care, relocation to neighbor islands, and biological control using a bacterium called Wolbachia.
With no impact on humans, a strong sterilizing effect on the invasive mosquitoes, and a long history of use in other countries, the Department of Land and Natural Resources claims that biocontrol utilizing Wolbachia could have tremendous impacts on the habitability of the island for forest birds.
However, even with regulators on the verge of approving such efforts on Kaua‘i, federal officials involved with the project have suggested the biocontrol measure likely wouldn’t be effective quickly enough to protect the ‘akikiki from extinction.
As conservationists run out of time to protect what few ‘akikiki remain on Kaua‘i, KFBRP has begun extracting the bird’s eggs until the island is once again more habitable.
Robby Kohley, director of aviculture with Pacific Rim Conservation who’s done conservation work across both the Hawaiian Islands and Alaska, notes the unique difficulties that Kaua‘i’s terrain and ecosystem creates.
“Each project comes with a different set of challenges,” he said. “The logistics problems of this project are quite high. Between the weather — mostly wet, muddy and incredibly steep — and the lack of luck ‘akikiki are having with nests this year, I’d say this one ranks really high on the challenge scale.”
Since late January, the recovery teams have been flying into the field and hiking to field camp. From there, they trudge through knee-deep mud on unimproved pig trails to reach ‘akikiki nests that had been previously scouted.
Using a camera mounted on a long pole, the members check the condition of the birds’ eggs — usually one or two per nest. If they appear to be in good shape, the team rigs up a tethered ladder system, sending one team member as high as 48 feet to extract them.
So far, the teams have rescued 10 ‘akikiki eggs, placing them in a portable incubator and gently carrying them up the trail to camp. The eggs are then flown to a brooder house in Koke‘e State Park before being transported to the San Diego Zoo Wildlife Alliance Keauhou Bird Conservation Center at Volcano on Hawai‘i Island.
However, in a typical season, the team finds closer to 30 nests, almost all of which fledge young into the wild — a far more hopeful scene than this year’s efforts.
“This year is an out of control level of nest failures,” Hite said.
Hite notes while ‘akikiki are very good at breeding in the wild, a one-two punch of avian malaria and predation by rats — another invasive species — has been particularly unkind to the birds this season.
“We spotted a female ‘akikiki sitting on two eggs,” he recalled. “And when we came back two days later to collect the eggs, we found broken, rat-chewed eggshells on the ground.”
As part of the ever-evolving battle against invasive species — an effort that goes hand-in-hand with honeycreeper conservation — the field team has now additionally begun setting dozens of rat traps to protect what few ‘akikiki nests remain.
However, such efforts are likely only delaying the bird’s inevitable demise. Following an eight-day stint in the field, Hite lamented the ecologically and culturally important ‘akikiki’s likely looming disappearance from Kaua‘i.
“These birds are only here,” he said. “They’ve been here the whole time, long before people arrived in the islands. They’re quiet, unassuming and wonderful. If we lose them, it’s a huge loss. It’s terrible.”
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Jackson Healy, reporter, can be reached at 808-647-4966 or jhealy@thegardenisland.com.
