干旱区生态环境知识资源中心

Geographical distribution and movement patterns of Cinnamon Warbling-Finch (Poospiza ornata) and Carbonated Sierra-Finch (Phrygilus carbonarius) in Argentina. - To establish the geographic distribution of a species it is necessary to ascertain the places where the species is likely to occur. However, it requires verifying whether its populations are sedentary, migratory, transient, or casual. In this study, we analyze the geographic distribution of two endemic emberizids in Argentina, the Cinnamon Warbling-Finch (Poospiza ornata) and the Carbonated Sierra-Finch (Phrygilus carbonarius). To study the residence status of the populations and movement patterns of these species we combine geographic information about the occurrence of the species with local information about abundance and mark-recapture studies in the central Monte desert. Analysis at biogeographic scale showed that both species mainly occur in arid and semi-arid environments of Argentina. The Cinnamon Warbling-Finch shows movements that correspond to short-distance migration. In contrast, movement patterns of the Carbonated Sierra-Finch are not so clear because the species is always present in its central distributional range. At local scale, in the central Monte desert, seasonal changes in abundance were consistent with the observed patterns in the geographic distribution and movement of both species. Banding of birds also showed that these species are highly mobile, at least in this region. Local results are consistent with the hypotheses that the Cinnamon Warbling-Finch is a nomadic species in its breeding range while the Carbonated Sierra-Finch exhibits temporal changes in the boundary of its southern breeding range. The combined analysis at different spatial scales allowed us to describe the movement patterns of Cinnamon Warbling-Finch and Carbonated Sierra-Finch. Also, it highlights the importance of having an accurate description of the seasonal geographic distribution of birds.