We studied the effects on structure of bird assemblages after replacement of native natural habitats by small-scale tree plantations used for recreational purposes. The richness and diversity were similar among habitats; however, the total bird abundance was greater in the tree plantations compared to the natural habitats. Also, we found that small-bodied birds that forage in the foliage had higher abundance in the natural habitats, while larger-bodied species that live in open spaces and forage on the ground occurred in higher abundance in the tree plantations. The comparative evaluation of the seasonal effect on avian assemblages of the contrasting habitats showed that natural habitats had a greater annual fluctuation of abundance values, while the tree plantations were more constant. Our study demonstrates that small-scale tree plantations for recreational purposes exert strong effects on bird assemblages, because they increase the abundance of the generalist and common bird species in the region.