Territorial behaviour and breeding in the Southern Antpipit Corythopis delalandi (Aves: Rhynchocyclidae) in southeastern Brazil

Abstract

ABSTRACT The Southern Antpipit is a terrestrial insectivore passerine that ranges in the undergrowth of semideciduous forests in central South America. Despite the historical interest on its disputed systematic position, no detailed study about its natural history is available. In this paper, we studied its territorial and breeding biology in southeastern Brazil. We studied colour-banded birds and closely monitored the nests found, estimating the home range using two distinct methods, the Minimum Convex Polygon (MCP) and the Kernel Density Estimator (KDE). The nest (n = 4) is a dome, somewhat elliptical in shape and with a side entrance, placed on the forest litter. Its structural layer is built with unidentified vegetable fibres, leaf petioles and horsehair fungus, and the external decorative layer is built with dry leaves and mosses. No well-defined lining layer was observed. Two eggs are usually laid and incubation, done solely by the female, lasts for 17 days. Both parents feed the nestlings, which fledge when 14–15 days old. Our data, together with citizen science data, reveal that the breeding season extends from August to December, therefore from the end of the dry season to the middle of the wet season. A mean home range size of 1.08 ± 0.44 ha was estimated using the MCP and of 1.42 ± 0.47 ha using the KDE (n = 9). The home range is defended against conspecifics, thus characterising an all-purpose territory, which is hold throughout the year, possibly during the entire reproductive life of the male.