Abstract
Aside from the positive benefits of wind energy, wind farms often bring environmental problems such as noise production and wildlife collision. However, little is known about the effects of wind farms on the ecology of tropical landbirds. In this study, we evaluated changes in bird-community diversity, composition, and structure directly beneath wind turbines, 200 m away from turbines, and in nearby croplands and secondary forests. In general, our results show (1) a gradient of species richness, with values highest in croplands and secondary forests, intermediate values 200 m from turbines, and lowest values beneath turbines, (2) fairly similar bird abundance for all treatments, with values highest in secondary forests in autumn and lowest 200 m from turbines in autumn, (3) bird communities highly similar at each season, but communities at 0 and 200 m from turbines differed strongly in autumn and communities at the rest of the studied sites differed strongly during both spring and autumn, (4) evenness of the bird community greater in secondary forests and croplands and lower at both distances from wind turbines, and (5) the area covered by croplands outside the wind farm played an important role, often related to increases in species richness. Our results also suggest that wind farms have a greater effect on wintering migrants than on residents; however, further studies are required for such a comparison to be tested robustly.