New Hope for a Rare Bird

Posted May 29, 2024 by Aimee Owen

Guam is a U.S. Island territory located about 1500 miles from the coast of the many island nations of southeast Asia.  It is home to the CHamoru people who are believed to have travelled to Guam from neighboring areas of southeast Asia around 1600 BCE, bringing their culture and language with them.  A particular part of that language is becoming more well-known in zoos across the United States since the 1980s.  The Guam kingfisher, or sihek in CHamoru, is an iconic species of Guam and a favorite among zoo professionals and guests alike here in the U.S.

The forests of Guam were once home to the sights and sounds of 12 different native forest bird species, including the sihek, living their lives and playing their role in this tropical paradise.  Today, only 2 of those species remain, leaving Guam’s forests much quieter these days.  The last sighting of a wild sihek was in 1988, but their story took a turn decades before.

In the era of World War II, the world watched as war raged across the globe.  All the while, the sihek, along with many other species native to the island of Guam, was just beginning a war of its own.  During this time, the brown tree snake was introduced to the island, most likely making its way on cargo ships.  The many small native species there were not accustomed to this type of predator and therefore succumbed quickly to the brown tree snake’s voracious appetite and lack of its own natural predators.  Once these numerous species of birds, bats, and lizards were completely eradicated by the snake, even Guam’s forest ecosystem suffered.  Many plants, including large trees, were unable to reproduce without the seed dispersal of these species.  The brown tree snake has also caused issues to Guam’s people in the years since then, causing power disruptions by climbing on power lines and getting into transformers and electrical boxes.  They have even been known to kill domestic chickens and small pets.

Today, there is an estimated total of 2 million brown tree snakes on the island of Guam, outnumbering its people 10 to 1.  The USDA captured 3,200 brown tree snakes on Guam’s Anderson Air Force Base last year alone.

Fortunately, the sihek is not alone in this fight.  In the early 1980s, conservation and governmental organizations in the U.S. and Guam captured remaining sihek and relocated them to U.S. zoos and aquariums to begin a breeding program in hopes of reintroducing Guam’s kingfishers back to their home once their numbers were adequate.  However, at the same time, efforts were being made to eradicate the brown tree snake from the island of Guam.  After years and countless attempts at removal, it was decided other routes of sihek conservation were necessary.

Fast forward to 2023.  After much work, U.S. Fish & Wildlife Services finalized a plan for the translocation of sihek to an experimental population on Palmyra Atoll, a small island south of the Hawaiian island chain.  And, lucky for the kingfishers, no brown tree snakes!  Once there, fledgling kingfishers will be held in a large aviary and then released.  Since these kingfishers have been extinct in the wild for nearly 30 years, there is a lot of information about their wild lives that we just don’t know.  Therefore, this experimental population will give scientists the opportunity to observe the birds’ abilities to survive in a wild setting, including watching for behaviors like hunting, breeding, and fighting illness or injury, all while we continue our fight against the brown tree snake in Guam.

And now, Cincinnati Zoo & Botanical Garden enters the picture.  The Cincinnati Zoo has a long history with the Guam kingfisher SSP (Species Survival Plan) and breeding program, caring for our first individual bird in 1982.  Over the years, kingfishers in our care here in Cincinnati have produced 28 chicks, many of which went on to be part of the breeding program as well.  In 2023, because of our success, Cincinnati Zoo’s Bird Department was chosen to play a critical role in this translocation project, and now again in 2024.

Currently, the Cincinnati Zoo is home to 2 breeding pairs of sihek, housed in our private “parent’s room” behind the scenes.  Our staff will be responsible for behavioral observations of our sihek, artificial incubation and management of any eggs produced, and transporting those eggs to the command center of the project, a quarantined hand-rearing facility at Sedgwick County Zoo in Kansas.

Sihek are a shy, secretive bird and require lots of privacy and quiet time, so even the management of our behind-the-scenes spaces has changed to ensure our sihek pairs are comfortable.  The last, but potentially most important, responsibility the Cincinnati Zoo bird staff has is raising sihek chicks!  Two bird staff from Cincinnati will be running the hand-rearing facility for a 2 week period during this process.

Once our eggs have arrived in Kansas along with our keepers, they’ll be hatched and raised for 30 to 40 days before they make the long journey to Palmyra and make history by becoming the first sihek in the wild in almost 30 years!

So far this year, the Cincinnati Zoo’s sihek parents have produced 10 total eggs and 3 chicks for the translocation project, with another on the way as we speak!  There is also potential for several more eggs to be produced before the season comes to a close.  Stay tuned for more updates as the Cincinnati Zoo’s birds and bird staff make bird history!