AN EXPERIMENTAL-STUDY OF NEST PREDATION IN A SUBTROPICAL WET FOREST FOLLOWING HURRICANE DISTURBANCE

We used artificial nest experiments to study rates and patterns of egg predation in subtropical wet and lower montane wet forest on the isla nd of Puerto Rico. Levels of depredation were higher for ground nests than for elevated nests, but we found no difference in rates of egg pr edation between forest edge (5-50 m) and forest interior (100-250 m) n ests. We quantified 25 forest vegetation variables surrounding ground and elevated, forest interior nests, and correlated nest success with these vegetation parameters. Utilizing discriminant function analysis, nest success was correctly classified in 59% of cases (for ground nes ts) using two Vegetation variables (shrub density and vegetation in th e 2.5-3.0 m foliage height class), and in 71% of cases (for elevated n ests) using six vegetation variables (canopy cover, vegetation in the 0-0.5, 0.5-1.0, 1.0-1.5, and 3.0-4.0 m foliage height classes, and Cec ropia tree density). Our data suggest that the absence of an induced e dge effect is the result of the creation of canopy openings and early successional vegetative associations in a matrix across the forest fol lowing hurricane disturbance in 1989. Comparative data suggest that th e high rates of egg predation recorded here may he typical for insular forest habitats.