Argentina (B), Brazil (B) (NB), Paraguay (NB) (P), Uruguay (B).
Breeds in north-eastern Argentina (Corrientes and Entre Ríos, possibly also Buenos Aires), extreme south-eastern Brazil (Rio Grande do Sul) and Uruguay (R Uruguay basin and south-eastern wetlands), possibly also south-eastern Paraguay. Migrates northern as far as south-central Brazil (north to southern Mato Grosso, southern Goiás and western Minas Gerais) and eastern Paraguay.
Rarity Status
Currently this species is not classified as a rarity in this country OR information has not been updated.
Population
Estimated population is 1,000 - 2,499 (2010) and decreasing.
Marsh Seedeater (Sporophila palustris) [XC49713]
by Rafael Antunes Dias from Alvear, Corrientes, Argentina (song)
Marsh Seedeater (Sporophila) [XC49709]
by Rosendo Fraga from Ruta 39, Corrientes, Argentina (song)
Subspecies
No subspecies.
Sporophila zelichi (Sibley and Monroe 1990, 1993) is no longer recognised following SACC (2009). It is now treated as a colour morph of Marsh Seedeater (Sporophila palustris).
Molecular evidence suggests that genus is closely related to Oryzoborus, which should perhaps be subsumed within it. Further, that both genera should be placed in the tanager family (Thraupidae). A molecular-genetic study of 17 species in genus, including ten in "capped" group ("capuchinos"), indicated that latter form two clades, a northern clade largely north of R Amazon containing Ruddy-breasted Seedeater (Sporophila minuta) and Chestnut-bellied Seedeater (Sporophila castaneiventris), and a southern clade consisting of present species and Copper Seedeater (Sporophila bouvreuil), Tawny-bellied Seedeater (Sporophila hypoxantha), Rufous-rumped Seedeater (Sporophila hypochroma), Dark-throated Seedeater (Sporophila ruficollis), Chestnut Seedeater (Sporophila cinnamomea) and Black-bellied Seedeater (Sporophila melanogaster). Determination of relationships within the southern clade not possible, as genetic differentiation very low and species are apparently part of a very recent and rapid radiation. Has been suggested that present species is a white-throated morph of Dark-throated Seedeater (Sporophila ruficollis) or a colour morph of Tawny-bellied Seedeater (Sporophila hypoxantha). In addition, form described as Narosky's Seedeater (Sporophila zelichi) (from Entre Ríos, in north-eastern Argentina) considered to be a white-necked morph of present species, to which it is vocally identical, and found in same habitat and at same locations as it; or possibly a hybrid between present species and Chestnut Seedeater (Sporophila cinnamomea).
BirdLife International Species Factsheet