Hidden Nests: Advances and Challenges in the Research and Conservation of Cavity-Nesting Birds in the Neotropics

By Cecilia Cuatianquiz Lima, María Gabriela Núñez Montellano, Eugenia Bianca Bonaparte, and Kristina L. Cockle

In the Special Feature Ecology and Conservation of Cavity Nesters in the Neotropics, seven field studies, a perspective, and a review contribute to understanding the ecology and conservation of cavity-nesting birds through a Neotropical lens. The Special Feature incorporates work from a wide diversity of Neotropical environments, from tropical rainforest to high desert and urban areas. It also describes policies and practices employed to improve equity and justice in the construction of ornithological knowledge. The Special Feature expands the possibilities for moving toward epistemic justice in ornithology and shows how the environment, avian excavator behavior, people’s attitudes, and management of trees and other plants interact to influence cavity availability and the ecology of cavity-nesting birds.

The Neotropics, extending from southern South America to central Mexico, is one of the most biodiverse regions in the world. It harbors more than a third of all bird species that rely on excavated or natural tree cavities for nesting, serving as important models for studies on forest management, land use, and ecosystem services. Sixteen years ago, Cornelius et al. conducted the first review of the ecology of cavity-nesting birds in the Neotropics, focusing on nest site limitation and proposing future research priorities. Since then, research on these communities has expanded and diversified. However, long-standing colonial biases in ornithology continue to exclude the ideas and contributions of people living and working in the Neotropics, which is not only unfair, but also hinders a comprehensive understanding of bird ecology (Soares et al. 2023).

Amplifying Neotropical Knowledge on Cavity-Nesting Birds

To promote and share knowledge about cavity nesters in the Neotropics, we organized a Special Feature on cavity-nesting birds in the journals of the American Ornithological Society (AOS), Ornithology and Ornithological Applications. Using sociocracy, we conducted a review (Bonaparte et al. 2024) that explores and synthesizes recent advances and current challenges in the study of these birds from a Neotropical perspective. In alignment with Ruelas Inzunza et al. (2023), we undertook a comprehensive review of articles published in regional journals across various languages, as well as theses and sources of Indigenous and local knowledge. Our collective workflow fostered equitable sharing of power and responsibilities within our research team (Cockle et al. 2025).

Listening to Neotropical communities

Studies from the Special Feature highlight that bird species can adapt their use of resources across various environments but face limiting factors such as wood hardness, cavity availability, and socioecological context. Long-term natural history observations of Xiphorhynchus fuscus (Lesser Woodcreeper) in Argentina’s Atlantic Forest reveal that this species excavates nest cavities in very large trees at advanced stages of decay (Cockle et al. 2024). A study from the Humid Chaco found that even large woodpeckers, despite their specialized anatomy for chiseling, were significantly constrained by wood hardness when selecting nest sites (Di Sallo and Cockle 2025). In the southern Chilean Andes, insects/fungi, and Pygarrhichas albogularis (White-throated Treerunner) played a key role as primary cavity creators for secondary cavity nesters, though cavity characteristics showed only a weak association with reproductive success (Cuatianquiz Lima et al. 2024). During passive restoration of secondary forests in the Brazilian Amazon, cavities became available within 18–30 years, but most were too low and small to accommodate large birds, such as forest-falcons and macaws (Dantas Oliveira et al. 2024). In Chile, an experimental increase in cavity availability resulted in higher densities of the cavity-adopting Aphrastura spinicauda (Thorn-tailed Rayadito) in forests degraded by selective logging, where nest sites appeared to be a limiting factor. However, in well-preserved forests—where cavity abundance was 1.5 times higher—this effect was not observed (Altamirano et al. 2024). In Mexico’s native dry tropical forests, Melanerpes chrysogenys (Golden-cheeked Woodpecker) excavated cavities in emergent, living Roseodendron donnell-smithii trees, whereas in coastal settlements, the woodpecker nested in dead coconut palms surrounded by vegetation (Maya-Elizarrarás et al. 2025). In Argentina’s Atlantic Forest, children named a high diversity of native cavity-nesting birds, but tended to overlook their key nesting habitats, suggesting an ongoing process of extinction of experience (Bonaparte et al. 2025).

The study and conservation of cavity-nesting birds require collective efforts from scientists, governments, and local communities. By taking intentional measures to conduct equitable work, we can promote fair, hospitable, and pluralistic ornithologies, and help ensure that cavity-nesting birds continue to fulfill their vital roles in the Neotropics.