INVESTIGADORES
RIVERA Luis Osvaldo
artículos
Título:
Availability of cavities for avian cavity nesters in selectively logged subtropical montane forests of the Andes
Autor/es:
POLITI NATALIA; HUNTER MALCOLM JR.; RIVERA LUIS OSVALDO
Revista:
FOREST ECOLOGY AND MANAGEMENT
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Año: 2010 vol. 260 p. 893 - 906
ISSN:
0378-1127
Resumen:
Tree cavities play a critical role in the life history
of cavity-using species and thus are an important structural feature of forests. Furthermore, some
common forest management practices can have a profound negative effect on
cavity quantity and quality. This is the first study to address cavity
resources in Neotropical montane forests and with this information we hope to
develop approaches to sustainable forest management that will assure the
conservation of cavity nesters. Our study design consisted of two treatments
(control and harvested forest) in both piedmont and cloud forests of the
subtropical montane forests of the Andes. This study indicates that cavities
are an uncommon feature even in control sites with only 3% of the trees
harboring cavities in both forest types. Even more uncommon are potentially usable
cavities for avian cavity nesters: only 0.15% of the trees have a potentially
usable cavity in the piedmont forest and only 0.42% in the cloud forest. In
logged forests there is a significantly lower density of potentially usable
cavities (4.12 vs. 0.51 cavities/ha in piedmont forest and 3.91 vs. 1.64
cavities/ha in the cloud forest). Furthermore, we documented a high loss rate
of potentially usable cavities (from 23 to 40%/year) that differs between tree
species and DBH classes. More specifically, in the piedmont forest, large,
decaying Calycophyllum multiflorum
have a relatively greater
probability of having potentially usable cavities, while in the cloud forest
potentially usable cavities are disproportionably found in large, decaying Blepharocalyx gigantea. In both forest types, snags are also very likely to
harbor a potentially usable cavity. In order for harvested stands in the
subtropical montane forest of the Andes to regain some of their ecological
value, it is necessary to retain trees that have potentially usable cavities
and also trees with the highest probability of becoming usable cavity trees.