Winter songs reveal geographic origin of three migratory seedeaters (Sporophila spp.) in southern Neotropical grasslands

ARETA JI

WILSON JOURNAL OF ORNITHOLOGY

WILSON ORNITHOLOGICAL SOC

Año: 2012 vol. 124 p. 688 - 697

1559-4491

The winter distribution of neotropical seedeaters (Sporophila spp.) known as capuchinos is poorlyknown. There are difficulties to understanding their migration patterns: fieldwork is lacking in their wintering areas, their?eclipse? plumages often make it difficult to identify species, different species share habitats during winter, and there is littleor no genetic differentiation of several forms. Vocalizations display a geographic signature (i.e., diagnostic acousticfeatures that are found in a limited area during the breeding period) and can be useful as indicators of a specific geographicorigin of a wintering bird. I present data that: (1) demonstrates that non-breeding male Dark-throated Seedeater (S.ruficollis), Rufous-rumped Seedeater (S. hypochroma), and Tawny-bellied Seedeater (S. hypoxantha) in wintering areas canbe assigned to a particular distant breeding population based on vocalizations; (2) evaluate the potential contribution ofvocal variation in other capuchinos to understand their migratory movements; and (3) use vocalizations to unravelmigration patterns of capuchinos. Non-breeding males of S. ruficollis from the Entre Rios regiolect were recorded inCerrado habitat close to Vila Bela da Santı´ssima Trindade, Brazil and in the Beni savannas close to Trinidad, Bolivia, S.hypochroma from the Corrientes regiolect was recorded close to Vila Bela da Santı´ssima Trindade, and S. hypoxantha fromthe Entre Rı´os regiolect was recorded close to Trinidad. Linking breeding and non-breeding areas through song-types isimportant to understand the evolutionary ecology and to promote conservation of these tiny long-distance flyers.