There's hope for a rare bird that's been extinct in the wild for 40 years. Eggs from a pair of Guam kingfishers have been spotted on an atoll in the Pacific Ocean where scientists are hoping to reestablish the birds.
The Guam kingfisher, or Sihek as it's called by the indigenous CHamoru people of Guam, was nearly wiped out by an invasive brown tree snake introduced accidentally by ships in the 1940s. Twenty-nine birds were captured in the 1980s and taken to zoos across the United States where a species survival plan was created in an attempt to save the species.
The zoos created a genetic database and began growing the captive population. Last March, nine eggs were sent to a biosecurity unit at a zoo in Kansas to prepare for reintroducing the species into the wild. Three of the nine eggs came from the Cincinnati Zoo.
"We're so proud. We were proud of it then; we're proud of it now; we'll be proud of it forever," Aimee Owen, senior aviculture keeper at the Cincinnati Zoo, tells WVXU. "The first chick of the project was [from] Cincinnati. Her name is 'Tutuhan' and she was the first chick to hatch, and is now the first youngster to produce eggs on Palmyra."
Guam remains an unsuitable habitat for reintroduction because the brown tree snake population is so high — only two native forest species remain on Guam, according to scientists in 2021 — so the birds are being introduced on Palmyra Atoll about 1,000 miles south of Honolulu, Hawaiʻi. The atoll is largely free of predators and is fully protected as part of several nature preserves, and by the Pacific Islands Heritage Marine National Monument, one of the largest swaths of ocean and islands protected in the world, according to the zoo.
The nine freshly hatched birds were released on the atoll in September 2024.
The birds were fitted with radio transmitters so researchers could track their progress. The batteries eventually died and researchers have been using cameras and observations to track the birds' progress.
"Of the nine birds, six of those birds, meaning three pairs, have started excavating nests," Owen says.
Researchers recently were able to capture photographs of the first two eggs laid in one of those nests.
"Those are from Tutuhan, who was our girl, and those are the first Guam kingfisher (Sihek) eggs in almost 40 years in the wild," Owen exclaims.
The Siheks' incubation period is about 21 to 23 days. That means, Owen says, based on when the zoo was notified about the eggs, they should be about ready to hatch.
"We have high hopes — cautiously optimistic is the phrasing that I would use. They are obviously first-time parents, so we'll just have to wait and see, but [we're] very lucky to be able to witness where they are so we can keep an eye on progress and making sure mom and dad are switching off incubation duties like they should, and all that good stuff."
The Nature Conservancy says there are plans to release more young Sihek at Palmyra Atoll this summer.
The ultimate goal is to someday reintroduce the Sihek to Guam.
"They're a huge cultural icon of the CHamoru people, and they're just an iconic species of the forests of Guam," Owen says.
Why the brown tree snake rattles some scientists
Efforts are underway to get rid of the brown tree snake. The Hawai'i Invasive Species Council estimates there are currently 10 to 21 snakes per acre, down from approximately 50 per acre at one time. That still adds up to some 2 million snakes. Voracious eaters, they've wiped out nearly all native forest bird species and three species of lizard, plus cause frequent power outages on the island.
There's been a concerted effort to keep the snakes from spreading beyond Guam to Hawai'i and the continental United States. However, there are concerns that work may be in jeopardy.
Hawai'i Public Radio reported in March that federal workers in Guam were being forced out of the facilities where they work to keep the snakes off of planes and ships departing the island. This came shortly after they were told their one-year contracts wouldn't be renewed, an action Hawai'i Public Radio says was later reversed.
In 2021, a researcher at the University of Cincinnati published research finding the brown tree snakes on Guam use a previously unknown climbing method, which may be how they got aboard ships to the island in the 1940s and '50s.
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