First record of free-living hyacinth macaw (Anodorhynchus hyacinthinus) eggs hatching using camera traps in southern Pantanal, Brazil

The hyacinth macaw is a social, monogamous, and nesting site faithful bird that lays an average of two eggs. The incubation time ranges from 27 to 30 days and begins after the first egg is laid, resulting in asynchronous hatching. This paper aims to describe the hatching process of free-living hyacinth macaw (Anodorhynchus hyacinthinus) eggs recorded using camera traps in the Pantanal biome of Brazil. Cameras were placed inside two artificial nests (nests-A and -B). Egg hatching was recorded during two reproductive periods in nest-A and nest-B. In both nests, only the complete hatching process of the first egg was recorded. In nest-A, the hatching processes showed a variation from 18 min to 16:30 h, and in the nest-B from 07:18 h. The hatching results of the hyacinth macaw eggs in nests- A and -B indicate no set time for the hatching event. The hyacinth macaw pairs assisted the hatchlings during the hatching process. Additionally, it was possible to hear the vocalization of the hatched nestlings during the event. This marks the first time that the hatching of free-living hyacinth macaw eggs has been recorded using camera traps. These records may open new horizons for research on reproductive behavior and embryonic development, significantly contributing to ex-situ conservation strategies for highly fragile species such as the hyacinth macaw.