Search

Some 263 birds were recorded near and in a 230-ha patch of semideciduous forest in cane fields of central São Paulo, Brazil. Subtracting 67 open-area species, 22 of marshes or creeks, 10 vagrants and 12 recorded later, 152 forest and border species were recorded in 1982-86, much like what was observed in a similar woodlot near Campinas. Both woodlots lost species gradually over the years. Some birds avoided hard cane-field edges, preferring soft bushy edges. Of open-area species, 22 seemed to have disappeared by 1997 due to earlier high El Niño rains or rare permanently open habitats in the sugar cane; 17 new species were mostly nocturnal ones not noted earlier, or occasional visitors. Forest and borders lost 31 species, gaining five of dry regions and one winter visitor. Several migrants from the south appeared only in wet years before recent greenhouse effects, some resident birds were hunted, and canopy hummingbirds were perhaps still present. Dry-forest travel-prone or "metapopulational" species moved their centers of distribution, partly concealing loss of moist-forest diversity.

We describe the opportunistic adaptation to man-induced changes in the habitats of six neotropical Caprimulgidae. Habitats created by those changes, and similar to their original and usual ones, are readily occupied by these nightjars. The occasional invasion of urban environments ("urbanization") is the most recent and most remarkable behavioural adaptation.