Forest recovery in post-pasture Amazonia: Testing a conceptual model of space use by insectivorous understory birds

POWELL, L.; NICHOLS, L.L.; HINES, J.; ZURITA, G.A.; STOUFFER, P.C.; JOHNSON, E.I.; WOLFE, J.D.

Baltimore

Congreso; 26 th International Congress on Conservation Biology; 2013

Society for the Conservation Biology

Although the Brazilian Amazon has lost more than 328,000 km2 of rainforest over the last 20 years, abandonment of deforested lands has created a vast network of secondary forests (SFs)?161,000 km2 by 2002?size of Florida. To quantify spatiotemporal patterns in space use of birds along edges of primary forest and a gradient of SFs (1?30 years old), we radio-tracked three understory insectivores at the Biological Dynamics of Forest Fragments Project: Glyphorynchus spirurus (n = 23), Xiphorhynchus pardalotus (n = 23) and Formicarius colma (n = 27). Birds in young SF had larger home ranges, core areas and movement rates than those in primary forest. G. spirurus was first to recover, showing no edge response to SF 11?14 years old; X. pardalotus recovered at 19?24 years and F. colma at 28?30 years. Young F. colma concentrated their activity along edges, just inside primary forest adjacent to young SF?these subordinates are likely pushed to edges by dominant adults, but are unable to penetrate young SF. Finally, using novel transition probability models in MARK, we estimated that even after 27?31 years, F. colma was still less likely to transition into SF from primary forest, suggesting that even our oldest SF had not yet recovered in terms of use by obligate rainforest species. By understanding the dynamics of movement by specialized rainforest birds, we will be in a strong position to conserve rainforest biodiversity as landscapes continue to change in the Anthropocene.