The Sihek (Guam Kingfisher) Finds Hope at Palmyra Atoll

Known as sihek by the Indigenous CHamoru* people, these colorful birds are native to Guam, where they have deep cultural and spiritual significance. But in the 1940s the arrival of an invasive species—the brown tree snake—led to the sihek becoming extinct in the wild, with the last wild sighting in 1988.

The loss of wild sihek in Guam is a tragedy. While the road to reintroducing them to their native forests is long, conservationists around the globe are working together to achieve this goal. Since the 1980s, the island bird has survived in conservation zoos and other wildlife facilities. Today, around 130 adult sihek are cared for at 25 zoos and institutions and a Guam Department of Agriculture facility, and preliminary efforts are underway to eradicate the brown tree snake on Guam’s Cocos Island, which could someday create a safe environment for the birds to return to Guam. In the meantime, the Sihek Recovery Program is working to establish a self-sustaining wild population at Palmyra Atoll where nine sihek are currently flying free. Hopefully more chicks will arrive soon!

*The CHamoru name is spelled with a capitalized H. Guam is spelled Guåhan in CHamoru.

Sihek chicks destined for Palmyra were hand-reared at a specialized quarantine rearing facility at Sedgwick County Zoo in Kansas. Several facilities contributed eggs to this effort, including Cincinnati Zoo, National Aviary, Disney’s Animal Kingdom, Brookfield Zoo and Sedgwick County Zoo.

On August 28, 2024, nine birds traveled from Wichita, Kansas to Palmyra Atoll. Scientists with TNC’s Island Resilience strategy and Zoological Society of London (ZSL) will be stationed on the remote atoll for the next five years to care for and monitor the birds while also collecting rare insights on how the species behaves in the wild.

Upon arrival, the sihek started eating right away, instinctually preened when they experienced their first rainfall and began hunting spiders, geckos and crabs. Once deemed healthy, each bird was fitted with a tiny radio tracker so the project team can monitor their movements as they leave the aviaries and settle in across the atoll. 

Thriving in the Wild

After their release, the four female and five male birds quickly explored their new home, learning how to forage and hunt new prey within the tropical forest. Four pairs have since established territories and built nests, three of the pairs have laid eggs and two pairs have laid multiple clutches of eggs.  

With the mated pairs just over a year old, this is their first time incubating and caring for eggs, meaning it’s likely it will take a few rounds of egg laying for the birds to hone their skills and hatch chicks. Nonetheless, these eggs demonstrate both the tremendous resilience of these remarkable birds and the power of conservation to create a second chance for species on the brink of extinction.

Participating AZA-accredited institutions across the U.S. are continuing to raise sihek. In the coming years, some of these chicks will also journey to Palmyra, with the ultimate goal of establishing 10 breeding pairs there. This project paves the way for a growing, wild sihek population for the first time since the 1980s.

Palmyra Atoll: A Refuge for Endangered Species

Sihek are being introduced to Palmyra Atoll because it is one of the most healthy land and ocean ecosystems on the planet, thanks to decades of protection and restoration work by TNC and partners. Located 1,000 miles south of Hawai‘i, the atoll is the only fully protected habitat for birds in the equatorial Pacific and comprises a spectacular marine wilderness. TNC purchased Palmyra Atoll in 2000 to preserve it and turned over the majority of the property to the U.S. Fish and Wildlife Service. As part of our Island Resilience Strategy, TNC maintains a globally significant preserve and research station at Palmyra.

Our work to remove invasive species like rats and restore native tropical forest has created a rare and wonderful opportunity at Palmyra: the atoll is free from invasive predators, incredibly wild and carefully monitored. It offers high-quality forest habitat suitable for sihek that is similar to their native forests. And extensive research shows that introducing the sihek will have minimal effects on native wildlife at Palmyra. All this makes Palmyra one of the only places in the world where conditions are suitable for the sihek to re-enter the wild. So far, they are thriving in their new home.