Effects of Cattle Grazing and Fire on the Abundance, Habitat Selection, and Nesting Success of the Bay-Capped Wren-Spinetail (Spartonoica Maluroides) in Coastal Saltmarshes of the Pampas Region

[摘要] Abstract. The Bay-capped Wren-Spinetail (Spartonoica maluroides, Furnariidae) is the most specialized and threatened bird inhabiting Spartina-dominated saltmarshes in southeastern South America. These marshes are being modified at an increasing rate, primarily by cattle grazing and fire, which make this spinetail highly vulnerable. To assess how land use affects the Bay-capped Wren-Spinetail, we estimated its density under different intensities of fire and cattle grazing, studied selection of nesting habitat and nest success, and experimented with nest predation to determine predation rates and types of predators. We found similar population densities, nest microhabitats, and rates of nest predation in marshes with a low intensity of or no grazing. In contrast, the species was absent from marshes with a high intensity of grazing and fire. Nest height was the best predictor of daily survival rates. Nest-predation experiments demonstrated that nest height affects predation intensity and predator type. Our r...

[学科分类] 动物科学

[关键词] furnariid;grassland;nest predation;Spartina densiflora;South America;Argentina;Spartonoica maluroides