Nest Site Selection and Productivity of a Critically Endangered Parrot, the Great Green Macaw (ara Ambiguus), in an Anthropogenic Landscape

Nest‐site selection is the principal way in which secondary cavity‐nesting species mitigate the negative effects of factors such as predation, parasitism and exposure on reproductive success. Large‐bodied secondary cavity‐nesting birds rely on large cavities in mature trees that are often absent or reduced in anthropogenically disturbed forests. Hence, the availability of high‐quality nest‐sites may be limited for these species, potentially reducing reproductive success. The aim of this study was to investigate nest‐site selection and the effect of nest‐site features on reproductive success in the critically endangered Great Green Macaw Ara ambiguus in northern Costa Rica. We show that Great Green Macaws select nest‐sites according to the characteristics of the cavity and the tree in which they are located. Moreover, reproductive success is a function of certain cavity features. However, the availability of high‐quality cavities, those with features associated with higher reproductive success, is potentially limited. By studying nest‐site selection and productivity together, we have identified that the availability of high‐quality cavities could potentially limit the future recovery of the critically endangered Great Green Macaw.