Biologists Rejoice as Extremely Rare Guam Kingfishers Lay Their First Wild Eggs in Nearly 40 Years The brightly colored birds are extinct in the wild, having disappeared from their native Guam in 1988 due to the introduction of the invasive brown tree snake. But now, they’re starting to make a comeback on Palmyra Atoll A female Guam kingfisher (left) and a male (right) perch on a branch on Palmyra Atoll. Martin Kastner A colorful bird that’s been extinct in the wild for nearly 40 years has been introduced on a new island in the Pacific Ocean—and the population has even started laying eggs. With help from conservationists, the Guam kingfisher (Todiramphus cinnamominus) seems to be settling in on Palmyra Atoll, a remote circular chain of 26 islets located halfway between Hawaii and American Samoa. Biologists are cautiously optimistic about the species’ future after discovering eggs in a nest roughly 12 feet off the ground on March 31. The birds use their powerful beaks to hunt skinks, geckos, spiders, beetles and land crabs. Martin Kastner The Guam kingfisher, known as the “sihek” to the Indigenous CHamoru people (previously spelled “Chamorro” on Guam before 2018), is a brightly colored, medium-sized bird with a long, thick beak. Males have cinnamon-brown feathers covering most of their bodies, but their wings and tails are a vibrant teal hue; females have pale white breast feathers. Sihek are skilled hunters that sit patiently on branches until they spot one of their favorite prey animals, including skinks, geckos, spiders, Once, sihek were abundant in Guam. But the introduction of the invasive brown tree snake, which wreaked havoc on the island’s native animals, decimated the species. The birds were declared extinct in the wild in 1988. Fortunately, before they disappeared forever, conservationists captured 28 sihek to establish a captive breeding population and keep the species alive. Now, some of their hard work is finally paying off. Last September, biologists released nine captive-bred Guam kingfishers—five males and four females—on Palmyra Atoll. Palmyra Atoll is roughly 3,600 miles east of Guam—not exactly near the bird’s native range. But biologists selected the site because it’s completely protected, located within the bounds of the U.S. Fish and Wildlife Service’s Palmyra Atoll National Wildlife Refuge and the Pacific Remote Islands Marine National Monument. In addition, Palmyra Atoll has been cleared of invasive species, like rats, that might prey on the birds. The Guam kingfishers on Palmyra Atoll were raised in captivity and released last fall. Martin Kastner The nine kingfishers hatched in various zoos and facilities across the United States, then were transported to the Sedgwick County Zoo in Wichita, Kansas, to be hand-reared by keepers. Once they were old enough, they made the 4,500-mile flight to a Nature Conservancy research station on Palmyra Atoll. They spent about a month getting acclimatized before researchers outfitted them with radio trackers and set them free. The birds’ long journey—both literally and figuratively—makes the recent discovery of wild eggs all the more impressive to biologists. “These birds were raised in captivity until last year,” says Martin Kastner, a biologist working with the Nature Conservancy and the Zoological Society of London on the Guam kingfisher reintroduction project, to Public Radio Guam’s Mia Perez and Naina Rao. “Now they’re foraging, nesting and even laying eggs on their own. It’s an incredible step forward.” Males have cinnamon-brown feathers covering most of their bodies, but their tails and wings are blue. Martin Kastner Kastner and two other biologists went to check on several known Guam kingfisher nests around the atoll on March 31. The first nest they looked at—inhabited by a pair known as Fuetsa and Sindålu—was empty. But when they reached another nest, created by birds named Tutuhan and Hinanao, they were ecstatic to find an egg. They used an endoscope camera to peer into the nest, where they saw “the perfect shape of a white egg just below the lip of the entrance hole,” Kastner writes on Instagram. It was the species’ first wild egg in at least 37 years. “It’s hard to describe the feeling at that moment, when decades of expectation and effort by zookeepers, biologists, administrators and most importantly the people of Guam, coalesce in an instant of joy and hope,” Kastner adds. “I’ve seen a few special things in my life, but this might always stay at the top of the list.”Five days later, when biologists checked the nest again, they spotted a second egg. They’ve since found eggs in two other nests, and they expect to find some in a fourth nest soon. The eggs weren’t a total surprise to Kastner, who in March had photographed the first siheks mating in the wild since the species went extinct. The team will continue monitoring the eggs to see how they progress. If all goes well, Palmyra Atoll may soon be home to hatchlings. But since the Guam kingfishers are all first-time parents, it may take a few rounds of egg-laying before any chicks hatch successfully, reports the Guam Daily Post’s Walter Ulloa. Biologist Photographs First-Ever Documented Sihek Mating in the Wild in Decades Watch on In captivity, Guam kingfishers typically only lay fertile eggs once they’re at least 11 months old. The birds on Palmyra Atoll are roughly 9 months old. Longer-term, biologists want to establish up to 30 breeding pairs of sihek on Palmyra Atoll. Zoos will continue sending hand-reared chicks until they reach that target. Another nine Guam kingfishers are slated to arrive this summer, for release in the fall. Their ultimate goal is to move beyond Palmyra Atoll and reintroduce the species to Guam—but they need to address the invasive brown tree snake problem first. “The number one mission needs to be, let’s bring them back to Guam,” Kastner tells the Guam Daily Post. “There’s no real other end goal than that in this project.” In the meantime, biologists are celebrating the egg-laying victory and reflecting on the work they’ve done for the species so far. “It’s a sign that really we are able to restore just about any species, just given the right kind of time and effort,” Kastner adds. “This is an extinct-in-the-wild species that a lot of people might have just given up on by the end, but there are some brave people that brought them into captivity.” Get the latest stories in your inbox every weekday.