Guam kingfisher parents rarely have success raising two chicks at the same time, so we moved one egg to a surrogate mother, Kahåya (ka-ha-ja). You may remember Kahåya from my previous updates. Though she has not successfully bred with her mate, Fuetsa (fu-et-sah), we have seen her diligently incubating infertile and “dummy” eggs (eggshells filled with plaster). She cared for her dummy eggs so well that we decided to give her a chance to rear one of Giha’s chicks — though Kahåya would think that the chick was her own. We gave her the egg to incubate on June 4. When we checked the egg a few days later, the hatching process was well underway.
We knew the chick would be out soon. From our camouflaged observation tents, we watched Kahåya closely. In the afternoon, she left the nest to eat. We checked the nest and saw the chick pushing itself out of the egg! Kahåya returned about 15 minutes later, poked her head out of the nest cavity with the chick in her mouth, and dropped it. We don’t know why Kahåya decided to drop the chick, but it’s not uncommon for Guam kingfishers to exhibit poor parenting. It’s what makes them one of our more difficult species to breed.
Luckily, the chick fell into an “egg-catcher” that we had set up for Kahåya last month after she laid an egg while sitting on a branch. We quickly retrieved the chick, so our veterinary team could examine it. We also collected its eggshell. The inner membrane of an eggshell contains many blood vessels, which we can test in a lab to determine the sex of a chick. The eggshell test told us this chick was a female. Thankfully, she received a clean bill of health, apart from a bit of bruising. Over the next several days, we fed her and monitored her progress.