Life history of the Mato Grosso Antbird Cercomacra melanaria in the Brazilian Pantanal

Here we describe the habitat use, reproductive biology, diet and details of the life history of the Mato Grosso Antbird Cercomacra melanaria , one of the least studied Cercomacra species. We located 30 nests, of which 22 became active and were monitored. The nest consists of a deep cup, placed among dense tangles of vegetation, almost always in forests of Vochysia divergens ( Cambarazal ). Eggs are pinkish-cream coloured, covered with reddish brown to purple spots and blotches that are concentrated around its centre and larger end. Average nest success was 32%. The Mayfield method indicated daily survival rates during egg and nestling periods of 0.94 and 0.96, respectively, and a success rate of 26%. Examination of 24 stomach contents revealed a diet based exclusively on arthropods.