INVESTIGADORES
COCKLE Kristina Louise
artículos
Título:
Persistence and loss of tree cavities used by birds in the subtropical Atlantic Forest
Autor/es:
COCKLE, KRISTINA L; MARTIN, KATHY; BODRATI, ALEJANDRO
Revista:
FOREST ECOLOGY AND MANAGEMENT
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Lugar: Amsterdam; Año: 2017 vol. 384 p. 200 - 207
ISSN:
0378-1127
Resumen:
An important goal for the conservation of tropical forest biodiversity is to maintain adequate supplies oftree cavities to support diverse communities of cavity-nesting and roosting vertebrates over the longterm, especially in human-modified landscapes. The conservation and replacement of nesting cavitiesdepend critically on cavity persistence, which is predicted to decline with increasing anthropogenicimpact to the habitat, and to vary according to characteristics of trees and excavators. We used Coxproportional-hazards models to study the factors influencing persistence of 277 cavities used by 43 speciesof nesting birds in 38 species of trees, across a gradient of human impact in the subtropical AtlanticForest of Argentina, 2004?2016. Median cavity persistence was 6 years, with 79% of cavity losses causedby the collapse of either the whole tree or the section of the tree holding the cavity. Contrary to predictions,cavity persistence did not vary across habitats (primary forest, degraded forest, farm) or excavatortypes (true woodpecker vs. weak excavator). Persistence was highest (median > 10 years) for nonexcavatedcavities in live trunks of healthy trees, and increased with tree size and species-specific wooddensity. Thus, although logging and conversion to farmland remove most cavities, the cavities thatremain in these human-modified habitats provide high quality, multi-annual nest sites for forest birds.Preserving and restoring these cavities should be a priority for conservation of forest vertebrates. Thepositive effect of species-specific wood density on cavity persistence suggests a trade-off in rates of cavityturnover, whereby cavities are produced early but lost quickly in fast-growing (low wood density)pioneer tree species, and produced late but persist much longer in slow-growing (high wood density)climax species.