Year-round presence of Slaty Thrush (Turdus nigriceps nigriceps) in mountains of central Argentina

VERGARA-TABARES, DAVID LAUTARO; ROJAS, TOBIAS NICOLAS

ARARAJUBA: REVISTA BRASILEIRA DE ORNITOLOGIA

SOC BRASILEIRA ORNITOLOGIA

Lugar: Pelotas, RS; Año: 2016 vol. 24 p. 329 - 334

0103-5657

The migration patterns of passerine species in the Neotropical region present several gaps of knowledge. The migratorybehavior of the Slaty Thrush (Turdus nigriceps nigriceps) has been well characterized in their central and northern distributionalong eastern slopes of the Andes from Argentina to Ecuador. The Slaty Thrush was historically considered a migrant breeder inthe southern extreme of their distribution. In the present study, we show new evidence of the resident status of this species in itssouthernmost distribution on western slopes of Sierras Grandes and Sierras de Comechingones in Córdoba Province, Argentina. There, the Slaty Thrush has a year-round presence only at sites invaded by fleshy-fruited alien plants. The main invasive plants form dense patches of vegetation and offer an abundant fruit supply that is highly consumed by this bird species during autumn?winter,when there are no native fruits available. We suggest that the Slaty Thrush was a migrant species in past decades, but the recentinvasion by fleshy-fruited species could explain its actual year-round presence by providing fruit in a period of the year of foodshortage and new suitable habitats.