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The articles presented in this special issue of Ecological Economics address the important theme of land use dynamics as it pertains to the Brazilian Amazon. Much environmental change is an ecological artifact of human agency, and such agency is often manifested in land use impacts, particularly in tropical areas. The critical problem of tropical deforestation is but one example of a land use dynamic; consequently, such problems are productively conceptualized in these terms. The present issue represents an explicit step in the direction of comprehending human encroachment into the...

We used artificial nest experiments to study rates and patterns of egg predation in subtropical wet and lower montane wet forest on the island of Puerto Rico. Levels of depredation were higher for ground nests than for elevated nests, but we found no difference in rates of egg predation between forest edge (5-50 m) and forest interior (100--250 m) nests. 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...

Bird populations in a subtropical wet forest were monitored every two to three weeks with mist nets and point counts beginning two weeks after the passage of Hurricane Hugo in September 1989. The results were compared with those of a pre-hurricane study in the same locations in which birds were sampled in forest understory and openings. Capture rates were initially higher than in the previous study, due to displaced canopy dwellers foraging in the understory. The shift of canopy dwellers may have obscured expected declines in nectarivores and fruit/seedeaters and contributed to increased...

The comparison of tropical birds having small clutches and long lifespans with temperate birds having large clutches and short lifespans is one of the cornerstones of theories dealing with avian reproductive strategies (Cody 1966, 1971, Stearns 1976, Ricklefs 1983, 1992, Murray 1985, Skutch 1985, Godfray et al. 1991). Karr et al. (1990) described the limited data supporting the assumption of long tropical lifespans and provided data for one sample of tropical birds--25 species from Panama--that did not show greater survivorship than a sample of temperate species (10 from Maryland). Their...