Reproducción y alimentación del género Sporophila (Emberizidae) en Argentina.

DI GIACOMO, ALEJANDRO G.; DI GIACOMO, ADRIÁN S.; REBOREDA, JUAN C.

Maturín, Venezuela

Congreso; VIII Neotropical Ornithological Congress; 2007

Neotropical Ornithology Society

The Neotropical genus Sporophila comprises approximately 30 species with stem gleaner specialization for seed eating. Information is scarce for the species of this group, in particular for those that inhabit the Southern Cone of South America. In Argentina there are 13 species, including five endemic and globally threatened. We studied the breeding biology and feeding behavior of eight of these species, including three endemic and globally threatened. We widely studied S. hypoxantha, S. caerulescens and S. collaris. We also described for the first time the nests of S. leucoptera and S. palustris, and present new data from very poorly studied species such as S. cinnamomea, S. ruficollis, and S. lineola. The group of “chestnut color” seedeaters (S. hypoxantha, S. cinnamomea, S. palustris, and S. ruficollis) nested in wet natural grasslands. The other species nested in other habitats: S. collaris in marsh vegetation (Cyperus spp.), while S. caerulescens, S. leucoptera and S. lineola nested in trees in the "Chaco" habitats. However, S. caerulescens and S. ruficollis also nested in vegetation of edges of crops in the Pampas agroecosystem. The observation of feeding events indicates that the eight species consumed mainly gramineous seeds (10 natives and three exotics). In particular, seeds of grasses of the genus Paspalum (5 species) were consumed by all species of Sporophila. S. collaris, also consumed seeds from several genus of marshy plants (non gramineous). In agricultural habitats, S. caerulescens and S. ruficollis consumed seeds from weeds and forage grasses. Our results indicate a close species-specific relationship between reproductive and feeding habits in the genus Sporophila.