20 September, 2024
By Alex Glass and Nico Arcilla
Male Black-faced Antbird, captured and released in Allpahuayo-Mishana National Reserve in 2023; this bird wore a uniquely-numbered band from a previous research project in 2010, indicating that this individual was at least 13 years old! Photo by Nico Arcilla.
Most of the world’s forests are logged for use as human commodities, and while many of these forests are lost forever, many recover and regenerate over time. However, much remains unknown about the impacts of prior disturbance on wildlife in regenerating forests, and in particular, how Amazonian birds respond to forest regeneration. Answering this question is the subject of a new publication co-authored by IBCP in collaboration with Alex Glass of Lees-McRae College. We used mist net capture data to compare bird communities in undisturbed tropical forest, selectively logged forest, and secondary forest regenerating on abandoned agricultural fields in the Allpahuayo-Mishana National Reserve, Peru. We found that after a 19-year recovery period, logged sites hosted similar bird communities to undisturbed sites, while forest regenerating from agricultural fields had lower bird species richness, with fewer insectivores and more nectarivores than other sites.
Alex Glass holds a male Blue-capped Manakin captured and released in Allpahuayo-Mishana National Reserve. Photo by Nico Arcilla.
Many Amazonian forest birds follow army ants to find food, and these ant-following insectivores declined with disturbance intensity as ground cover vegetation increased, while hummingbirds and other nectarivore abundance increased as tree density decreased. Our results suggest that selectively logged forests can regain pre-disturbance bird diversity and vegetation structure within two decades, provided that they are protected from further disturbance and located near undisturbed forest. Increasing tree density and decreasing ground-level vegetation in secondary forests regenerating from agricultural fields, which may take much longer to fully recover. However, these sites still supported many forest species, including Black-faced Antibird (Myrmoborus myotherinus) and Blue-capped Manakin (Lepidothrix coronata), and provide important habitat for many other forest species, thanks to conservation efforts by the Peruvian government to protect this area, with its rare Amazonian white-sand forests.
Gray-capped Flycatcher (Myiozetetes granadensis) captured and released in Allpahuayo-Mishana National Reserve. Photo by Nico Arcilla.