There are about 140 Guam kingfishers left in the entire world. Eighteen of these brightly-colored birds live in Front Royal, as part of a breeding program run by the Smithsonian's National Zoo and Conservation Biology Institute, which aims to reestablish the birds in the wild. WMRA's Randi B. Hagi reports.
This is the call of a bird that's been extinct in the wild for nearly 40 years.
[sound of sihek calls]
The Guam kingfisher, or sihek, was wiped out from its island home by the invasive brown tree snake. In the 80s, biologists rescued the last remaining 29 birds to start a managed breeding program – and of those, only 16 bred. Their offspring now live at the Smithsonian's Front Royal campus dedicated to studying and saving endangered species, and another two dozen breeding program facilities in the continental U.S. and Guam.
ERICA ROYER: It is about a robin-sized species of kingfisher, also called the sihek, in CHamoru, and they actually don't eat fish. … They primarily are eating invertebrates and small mammals, and small reptiles. … They're orange and blue, and the females have a white chest and the males have an orange chest.
Erica Royer is an aviculturist with the Smithsonian, and an expert on sihek – which means she does everything from tracking the genealogy of every one of these birds on earth, to feeding baby birds by hand every few hours. When full-grown, their sturdy beaks loom large on their brightly colored little bodies.
ROYER: They'll actually grab their prey and stun it, so most of the prey we feed is already frozen-thawed food. They do get some live food. But they'll stun the deceased food as well, so they'll pick it up and smack it on a branch a bunch of times. I like to think of it as they're tenderizing their food! But the beak, also, is really good for excavating. So these guys are cavity nesters. … They would normally, in the wild, be excavating semi-rotten palm logs.
Inside one room in the facility's small animal building, two juveniles – 19 and 20 days old, respectively – await a meal of mouse, lizard, mealworms, and crickets.
ROYER: Extra special delicacy for a sihek!
She feeds the youngsters with tweezers, whistling to tell them it's mealtime, and the chicks respond with a throaty chirp.
[Royer whistles, chicks call out]
We walk into the adult and adolescent wing, where the air is warm and humid, and tall enclosures are filled with foliage. The sihek occasionally get live mice or crickets for enrichment.
[sound of crickets chirping]
The birds are very skittish around people, so a radio plays quietly to help them tolerate some proximity to humans.
ROYER: Most of them are pretty shy. There are a few spicy ones, and when they have a nest or eggs, they are a lot more spicy. They'll try to divebomb me in the head while I'm trying to check their nest.
Carefully selected breeding pairs live in side-by-side enclosures before they're fully introduced.
ROYER: They are a territorial species. And so you'll see some hunting blinds in the hallway here. That's where I observe the birds from so that they can't see me. So we'll put birds together and assess behavior to make sure there's no aggression. There are sometimes divorces.
That's another one of Royer's responsibilities: being an avian Dr. Ruth.
ROYER: I want to see them singing together and excavating together, and, just in general, looking relaxed around one another. You can kind of tell when things start to go downhill if they start looking tense or they start leaving some food. … We'll sometimes give them a break and then try again … or, sometimes, changing their environment, so moving them to a new territory, that's actually what worked for these guys. I tried them very briefly last year and they did not get along, and I put them in a different space.
The couple – Antonio and Poki – have now produced four chicks since getting their new digs. Royer separated another couple that wasn't getting along, but then the female laid an egg.
ROYER: We don't know how long they can store sperm, so I have had a pair that was separated for four or five days and the egg was fertile … so I'll check it in a couple days to see. If it is, this pair, their chicks are slated for Palmyra.
That's Palmyra Atoll – a ring of islets in the Pacific about 3,600 miles away from Guam as the crow, or sihek, flies. Because brown tree snakes are still in the kingfishers' native home, biologists have established a tiny, experimental population of them on Palmyra instead. In 2024, nine birds were released on the atoll – they're all still alive, and they've laid eggs, but haven't hatched any chicks yet. Royer is hopeful they might have enough chicks in captivity this year to take more out into the wild.
ROYER: This is a species that we do feel like it is possible to return them home. We've gotten to the point now where we have been able to do wild releases, and before that we weren't sure, entirely, how the birds would do. You would expect, with a translocation like this, that maybe you'd see a 50% survival rate, but we still have 100% survival … so we know that part is possible, right? We know now what we need to and don't need to do to prepare them.
They have two more fertile eggs incubating as we speak – within them, the possibility of getting two steps closer to wild-born sihek flying free once more.
