Moucherolle à ventre bai

The Chocolate-vented Tyrant (Neoxolmis rufiventris) is a medium-sized flycatcher in the family Tyrannidae, native to the open grasslands and steppes of southern South America, principally Patagonia and the Pampas of Argentina and Uruguay, with occurrence in southern Chile. The tyrant flycatchers are the largest family of birds in the world, and Neoxolmis represents a group of ground-associated tyrannids adapted to open, treeless landscapes. The Chocolate-vented Tyrant is named for its rufous to chocolate-brown vent and undertail coverts, which contrast with the otherwise grey, brown, and white plumage. It forages on the ground and from low perches, capturing insects and other invertebrates, and nests in cups on or near the ground among sparse grass. It is a partial migrant, with some populations moving northward from Patagonia during the austral winter. The IUCN classifies this species as Least Concern; it has a relatively broad range in Patagonian and Pampas grasslands, habitats that, while threatened by agricultural intensification and exotic grass invasion, still extend over large areas. Like most open-country tyrannids, its populations are sensitive to conversion of native grassland to cropland or afforestation with exotic trees.