From Hatch to Fledge: Growth and Development of Sihek (Todiramphus cinnamominus) Chicks at Brookfield Zoo Chicago

Until recently, the sihek (Guam kingfisher, Todiramphus cinnamominus) has persisted entirely in managed care since a breeding program was established in the 1980s. Understanding the growth and developmental milestones of the sihek from hatch to fledging is critical to enhancing conservation efforts and improving management practices that promote positive welfare. In this study, we summarized data collected on the growth patterns, developmental milestones, and rearing differences in sihek chicks raised at Brookfield Zoo Chicago from 1989 to 2023. We found that hand-reared chicks reached the fledging stage significantly earlier than parent-reared chicks that received supplemental feeding from staff. Additionally, we found that hatch weight was a significant predictor of survival to fledging, highlighting the importance of collecting weight data at all stages of life. These insights into sihek development in managed care provide important data for the development of welfare-focused management practices that improve the success of conservation efforts while also prioritizing the wellbeing of each individual chick.