First record of a four-egg clutch of Collared Forest Falcon Micrastur semitorquatus, with notes on a nest in a building in southern Brazil

Summary. Collared Forest Falcon Micrastur semitorquatus ranges from northern Mexico to southern Brazil. This species is known to lay 1–3 eggs. We describe the first four-egg clutch for M. semitorquatus from observations made in southern Brazil, in the state of Santa Catarina. We also describe the nest site, nestling diet and assess sex ratio and mass gain of the nestlings.