Nest box placement influences occupancy by Yellow-headed (Amazona oratrix) and White-fronted (Amazona albifrons) Parrots in the pine savannas of Belize

Abstract

Supplementation of nest boxes is a common practice to increase nesting opportunities for cavity nesters, such as psittacids (i.e., parrots), many of whom are species of conservation concern. However, understanding occupancy requirements of most psittacids remains an important challenge for effective conservation actions, including placement of nest boxes in the landscape. This study utilized logistic regression models to investigate factors that influence occupancy of nest boxes by two Amazon parrots in the lowland pine savannas of Belize. We performed combined and separate analyses of nest box occupancy by White-fronted (<em>Amazona albifrons</em>) and Yellow-headed Parrots (<em>Amazona oratrix</em>), in relation to understory cover, localized tree density, frontal visibility from the nest box entrance, tree height, tree canopy cover, nest box entrance orientation, and tree diameter at breast height. Overall, 60% of nest boxes were used by four species of Amazon parrots, with White-fronted and Yellow-headed Parrots accounting for majority of use; 27% and 28%, respectively. Tree height had a strong positive effect on nest box occupancy in the combined species analysis. Species-specific analysis revealed that Yellow-headed Parrots occupied nest boxes in taller trees, closer to previously successful nests, while White-fronted Parrots did not show strong preference for any measured characteristics. Our results demonstrate that these two species will utilize artificial nest boxes and specifically highlights the importance of selecting taller trees when installing nest boxes for use by Yellow-headed Parrots.