Avian responses to restoration: Nest-site selection and reproductive success in song sparrows

Riparian habitats typically support high diversity and density of both plan ts and animals. With the dramatic loss of riparian habitats, restoring them has become a priority among conservation practitioners. Diversity and dens ity of avian species tend to increase following riparian restoration, but l ittle is known about holy restored habitats function to meet particular spe cies' needs. Habitat structure is an important factor affecting species div ersity and density and can influence nest-site selection and reproductive s uccess. To evaluate habitat restoration, rye examined interactions between habitat structure, nest-site selection, and nesting success in Song Sparrow s (Melospiza melodia) nesting in restored, mature, and young naturally rege nerating stands of riparian forest. We found that stand types differed mark edly in structure, and that habitat structure influenced both nest-site sel ection and rates of nest loss to predation. Comparison of habitat structure among the three stand types indicated that restored stands offered fewer a cceptable nest sites and poorer protection from nest predation. Concordant with those differences in habitat structure, Song Sparrows showed trends to ward less density in restored stands than in mature forest, and had poorer nesting success as a result of predation.