Topic
Xanthopsar flavus
About: Xanthopsar flavus is a research topic. Over the lifetime, 6 publications have been published within this topic receiving 52 citations.
Papers
TL;DR: Based on 21,518 km of road surveys, the Argentinian range of the endangered Saffron-cowled Blackbird Xanthopsar flavus now seems confined to two small and disjunct areas in Corrientes and Entre Rios provinces, north-east Argentina as discussed by the authors.
Abstract: Based on 21,518 km of road surveys, the Argentinian range of the endangered Saffron-cowled Blackbird Xanthopsar flavus now seems confined to two small and disjunct areas in Corrientes and Entre Rios provinces, north-east Argentina. In Corrientes the species inhabits natural pastures and rice-fields; in Entre Rios agropastoral land. Estimates based on numbers of localities and flock sizes suggest a Saffron-cowled Blackbird population of 500–1,000 individuals. This blackbird is highly gregarious. Mean flock size (n = 30, non-breeding period) was 31.9 birds (range: 6–102), and was significantly larger in Entre Rios. In Corrientes foraging blackbird flocks associated mostly with the Black-and-White Monjita Xolmis dominicana, in Entre Rios with the Brown-and-Yellow Marshbird Pseudoleistes virescens. Nesting in both provinces was colonial, with up to 24 nests in a 0.43 ha plot. Nests were built in native and introduced herbaceous plants. The Shiny Cowbird Molothrus bonariensis parasitized 29.2% of the nests in one colony; its eggs and chicks are larger than those of the host. Plausible reasons for the species's extinction or decline at a local level are drainage of wetlands (south-west Buenos Aires Province) and the replacement of pastures with pine and eucalypt plantations in Corrientes. General threats include trapping for the pet trade and increased cowbird parasitism. Flocks below a minimum size may not be viable. An urgent measure of protection would be the fencing and preservation of traditional colony sites.En base a 21.518 km de censos de rutas parece que la distribution actual del amenazado Tordo Amarillo o Dragon Xanthopsar flavus en Argentina esta limitada a dos pequenas areas disyuntas en las provincias de Corrientes y Entre Rios. En Corrientes la especie se encuentra en pasturas naturales y arroceras, mientras que en Entre Rios usa campos agricola-ganaderos. Una estimation basada en el numero de localidades y tamanos de bandadas indicaria una poblacion total de 500 a 1.000 individuos. El tamano promedio de bando (n = 30, periodo no reproductive) fue 31,9 individuos (rango 6–102) y es significativamente mayor en Entre Rios. En Corrientes las bandadas se asocian principalmente con la Monjita Dominica Xolmis dominicana, y en Entre Rios con el Pecho Amarillo Pseudoleistes virescens. La nidificacion fue colonial en ambas provincias, con una densidad de hasta 24 nidos en 0,43 ha. Los nidos se construyeron en plantas herbaceas nativas y exoticas. El Tordo Renegrido Molothrus bonariensis parasito 29,4 % de los nidos de una colonia, siendo sus huevos y polios significativamente mayores. Posibles razones para la extincion y declination a nivel local de la especie serian el drenaje de humedales (SO de Buenos Aires) y el reemplazo de pasturas por bosques implantados de pinos y eucaliptos (Corrientes). Las amenazas a nivel generales incluyen la captura para el comercio de aves de jaula, y un mayor parasitismo de cria. Una medida urgente de protection de la especie seria cercar y preservar sitios tradicionales de nidificacion.
35 citations
TL;DR: In this paper, the authors studied the Saffron-cowled Blackbird Xanthopsar flavus at the Banhado do Vinte-e-Cinco (BVEC) and Banho da Mulata (BDMC) area, in Rio Grande municipality, Rio Grande do Sul state, Brazil.
Abstract: Saffron-cowled Blackbird Xanthopsar flavus is a globally threatened icterid of open areas of south-eastern South America. Several sources suggest that the species is declining throughout its range, mainly due to habitat destruction. Between December 1997 and December 1999 we studied a breeding population of X. flavus at the Banhado do Vinte-e-Cinco and Banhado da Mulata area, Rio Grande municipality, Rio Grande do Sul state, Brazil. This population, previously unreported for the state's coastal plain, numbers at least 60 individuals and seems confined to an area of c. 35 km2. The area is characterized by Cyperacaea-dominated peat marshes in comparatively higher terrain, covered with sandy, rolling fields. The species was recorded in all months (not necessarily of the same year) except March, and a marked irregularity in flock size was detected. During the non-breeding period, flock size averaged 12.7 individuals (S.D. = 11.7; range = 2-37; n = 11). During the 1997-1998 breeding season (December to January), mean flock size was 25.3 individuals (S.D. = 16.2; range = 16-60; n = 7), while in the 1998-1999 and 1999-2000 breeding seasons, 33 and 4 individuals were recorded respectively. No pronounced discrepancy was found in the size of the largest flocks recorded per season (from 20 to 37 individuals), suggesting that the population is sedentary and that it undertakes only local movements. A nesting colony occupying the same part of the marsh in two successive breeding seasons was composed of six breeding pairs in 1997-1998, with an estimated nesting success of 31.8-36.3% at fledgling time. The species is highly gregarious and sociable, foraging flocks frequently following individuals of Black-and-White Monjita Heteroxolmis dominicana and, to a lesser extent, Yellow-rumped Marshbird Pseudoleistes guirahuro and Brown-and-yellow Marshbird P. virescens. Although habitat loss has been indicated as the main factor for the species' decline, we suggest that habitat perturbation and modification may affect negatively recruitment rates in the species and, theoretically, its overall population size. Furthermore, the conservation of Rio Grande's peat marshes should be regarded a regional priority, in order to preserve threatened birds and a very unusual wetland type.
13 citations
TL;DR: In this paper, a grassland fire experiment aimed at evaluating the effect of grassland fires on foraging (grasses) and breeding (marshes) habitat use by the Saffron-cowled blackbird Xanthopsar flavus is presented.
Abstract: In the world scenario of declining grassland bird populations, South American species are a particular concern. The Saffron-Cowled Blackbird Xanthopsar flavus is endemic to grasslands in Central and southern South America and its status is vulnerable. Natural history studies stress a number of factors responsible for the decline in its populations. In this paper, we present results from a grassland fire experiment aimed at evaluating the effect of grassland fires on foraging (grasses) and breeding (marshes) habitat use by the Saffron-Cowled Blackbird in a region where fire has been used for centuries as a tool for cattle management. We compare burned grasslands with a control treatment and grasslands within a conservation unit, evaluating uses before and after burning as well as relating bird abundance with environmental characteristics. We found that the Saffron-Cowled Blackbird used the burned treatments more frequently and avoided habitats with tall grasses and developed vegetation. Thus, this species is absent from the conservation unit, which has not experienced fires in nearly three decades. The Saffron-Cowled Blackbird depends on the existence of marshes (breeding habitat) surrounded by short grasses (foraging habitat). In the study region, short grasses are a result of burning practices. As the burning period coincides with the breeding season, the lack of criteria on the part of landowners regarding how to apply and control fire poses a permanent threat to these populations.
9 citations
Journal Article•
TL;DR: Fraga et al. as discussed by the authors presented the Centro de Investigaciones Cientificas y Transferencia de Tecnologia a la Produccion.
Abstract: Fil: Fraga, Rosendo Manuel. Provincia de Entre Rios. Centro de Investigaciones Cientificas y Transferencia de Tecnologia a la Produccion. Universidad Autonoma de Entre Rios. Centro de Investigaciones Cientificas y Transferencia de Tecnologia a la Produccion. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Santa Fe. Centro de Investigaciones Cientificas y Transferencia de Tecnologia a la Produccion; Argentina
3 citations
TL;DR: The discovery of helpers at eight of nine nests of Yellow-rumped Marshbirds from northeastern Argentina and Paraguay suggests that cooperative breeding in the Icteridae has a phylogenetic component.
Abstract: We found helpers at eight of nine nests of Yellow-rumped Marshbirds (Pseudoleistes guirahuro) from northeastern Argentina and Paraguay. From one to four helpers were observed during the incubation and nestling periods, but during nest building we saw solitary pairs. The helpers, of unknown sex and age, provisioned food to the chicks and defended the nest against several raptors. The Yellow-rumped Marshbird had a similar breeding system to its congener the Brown-and-yellow Marshbird (P. virescens) except that the former did not nest in colonies. According to a recent molecular phylogeny both Pseudoleistes marshbirds plus the Saffron-cowled Blackbird (Xanthopsar flavus) form a well-defined clade. All three of these species have helpers. This result suggests that cooperative breeding in the Icteridae has a phylogenetic component. Cria Cooperativa de Pseudoleistes guirahuro en Argentina y Paraguay Resumen. Encontramos ayudantes en ocho de nueve nidos de Pseudoleistes guirahuro presentes encontrados e...
3 citations
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Performance Metrics
| Year | Papers |
|---|---|
| 2017 | 1 |
| 2010 | 1 |
| 2008 | 1 |
| 2004 | 1 |
| 2002 | 1 |
| 1998 | 1 |