Marsh seedeater (Sporophila palustris)

GenusSporophila (1)
SizeLength: 10 cm (2)

The marsh seedeater is classified as Endangered (EN C2a(i)) on the IUCN Red List 2004 (1).

This seed-eating bird is thought to have until very recently been the same species as either the grey-and-chestnut seedeater (Sporophila hypochroma) or the Entre Rios seedeater (Sporophila zelichi), but is in the process of speciation; becoming a genetically different species. Males of this small finch species are distinctive. They have a white throat, cheeks and upper breast, contrasting with reddish-brown underparts and rump. The neck and crown are grey and the wings and tail are dark grey with a white patch at the base of the primaries. Females are dull brown and are not distinguishable from females of other species of Sporophila. The marsh seedeater calls with feisty, high-pitched whistles and ‘chiuu’ sounds (2).

The marsh seedeater breeds in Argentina, Brazil, Uruguay and possibly southeast Paraguay. It winters in Brazil and migrants have been seen in east Paraguay and north Argentina (2).

Breeding amongst wet grasslands and marshes, the marsh seedeater is less fastidious about its habitat in winter and during the migration, inhabiting both wet and dry grasslands (2).

Although normally active during the day, the male may sing at night during the breeding season, as he tries to attract females and defend his territory. When singing, the male chooses a prominent spot, points his beak vertically and ruffles his feathers. He will also fight with and chase away other males. Whilst thought to be mainly socially monogamous, marsh seedeaters are known to mate promiscuously when the population is at high density. Once laying has taken place, pairs remain faithful; the female incubates the eggs alone, but the male joins her in feeding and caring for the nestlings (3).

The marsh seedeater balances on tall grasses to pick seeds from the seed heads, and consumes no other food (3).

The main threat to this species is collection for the caged bird trade. This practice has severely reduced population numbers and has resulted in the loss of the marsh seedeater from many areas of Argentina, and it seriously threatens the survival of populations in Uruguay. Breeding site habitat degradation due to intensive cattle grazing, afforestation with eucalyptus and pine, pesticide contamination, and drainage for agriculture, particularly in southeast Uruguay, have contributed to population declines. Mechanised agriculture, invasive grasses and annual burning are proving detrimental to the marsh seedeater in its wintering habitat (2).

The marsh seedeater is legally protected in Brazil and Uruguay and collection is illegal in Argentina. It breeds in Potrerillo de Santa Teresa Reserve, Uruguay and Ibera Provincial Reserve in Argentina. It winters in Emas National Park, Brazil and migrating birds are found in several reserves in Paraguay and Argentina. Crucial to the survival of this species is the effective prohibition of trapping in all range states, and the removal of incentives to afforest with eucalyptus and pine. It may also benefit from being added to the Convention on Migratory Species (CMS or Bonn Convention) (2).

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:

  1. IUCN Red List (July, 2014)