Breeding biology of the Ochre-breasted pipit (Anthus nattereri), with notes on its conservation in the Upper Rio Grande Grasslands, south-eastern Brazil

Abstract

ABSTRACT The Ochre-breasted pipit Anthus nattereri is a terrestrial bird restricted to natural grasslands of south-eastern South America. The species is globally Vulnerable to extinction and its natural history is still poorly known. We investigated the breeding biology of Ochre-breasted pipits, commenting on its habitat use and the potential impacts of local grasslands management practices with fire on the species’ conservation. Fieldwork took place mainly between January and December 2016 in the Upper Rio Grande Grasslands, south-eastern Brazil. Five nests of the species were found between September and November, one of them recently destroyed by fire. Nests were cup shaped and placed on the ground, being built with dry grasses, resembling the pattern documented for other species of Anthus. The eggs were covered with brownish spots and dots to a variable extent and the background colour ranged from greyish white to brownish white. The egg colour pattern also fell within the known range of variation for congeneric species, as did the clutch size (two to three eggs) observed in tropical species of Anthus. Ochre-breasted pipits tended to occupy nesting sites with higher and denser grass cover (eg small patches of vegetation that survived the last fire event) when compared to non-nest sites located in adjacent recently burned areas, which potentially suggests a preference for such habitat attributes. Although the Ochre-breasted pipit is relatively common in the study area, the highest temporal incidence of fire coincides with its breeding season, which can directly impact the local population through the burning of nests and the elimination of suitable nesting sites. Thus, it is important to conduct long-term studies to evaluate the impact of different fire regimes on the reproductive performance of Ochre-breasted pipits, thus allowing the design of better ecosystem management practices to guarantee its conservation.