Diversity and Habitat Distribution of Birds in Coastal Marshes and Comparisons with Surrounding Upland Habitats in Southeastern South America

Abstract

We studied variation in bird assemblages with plant associations for three different coastal marshes from Southeastern South America (SESA) and assessed how marsh bird assemblages related to nearby upland bird assemblages. We surveyed bird species and plant structure along the tidal gradient of each locality from the low tide level to the upper habitats bordering coastal marshes. Twenty species frequently used coastal marshes, including relatively few migratory species. We found that birds occurring in SESA coastal marshes do not have distributions constrained to coastal marshes. Nonetheless, four bird assemblages were recognized in association with vegetation types and/or sites. Among the recorded coastal marsh species, the bay-capped wren-spinetail (Spartonoica maluroides) is both the most frequent and the most habitat constrained. Bird richness increases steadily along the tidal gradient associated with the increase in vegetation structure, suggesting that bird richness is directly explained by vegetation and indirectly by the physical conditions influencing vegetation structure. Results highlight the importance of SESA middle marshes as habitat for conservation of some threatened SESA grassland birds.

Causes and Consequences of Nest Mass and Structure Variation in the Bay-Capped Wren-SpinetailSpartonoica maluroides

“…Particularly, saltmarshes dominated by Spartina densiflora (~0.8 m height) are shorter than other tall-grasslands adjacent to the marsh (e.g. Cortaderia selloana~1.5 m; Isacch et al 2014). So that the range of heights at which Wren-spinetail nests may be placed is relatively narrow (~40 cm, Cardoni et al 2012) compared to other grasslands of the same region (~1.5 m, Isacch et al 2014).…”

“…Cortaderia selloana~1.5 m; Isacch et al 2014). So that the range of heights at which Wren-spinetail nests may be placed is relatively narrow (~40 cm, Cardoni et al 2012) compared to other grasslands of the same region (~1.5 m, Isacch et al 2014). This may determinate a trade-off between the effect of flooding and ground predation (affecting nests placed in lower strata) and the effect of aerial predation (affecting nests placed in higher strata).…”

“…Limnornis curvirostris, Limnoctites rectirostris, Phleocryptes melanops, Cranioleuca sulphurifera; Narosky et al 1983, de la Peña 1988, thus indicating either phylogenetic constraints on nest architecture evolution or differences in the characteristics of nest sites. In any case, evolution seems to have favored a flexible strategy in Wren-spinetail in terms of the nest architecture, as a possible adaptation to live in a structurally variable environment, such as saltmarshes (Cardoni et al 2013, Isacch et al 2014.…”

Diversity of Tetrapods in a mosaic of southeastern environments of the Pampean ecoregion as a tool for conservation planning

“…Vega & Bellagamba, 1990Vega & Bellagamba, 1990, Vega, 2001b, Vega et al, 2008Isacch et al, 2014Mora & Mapelli, 2011, Chimento & De Lucca, 2014Pastizales Vega & Bellagamba, 1996, Vega, 2001a, Vega, 2001aComparatore et al, 1996, 2014, Martínez, 2001, Baladrón, 2010, Pretelli et al, 2013Comparatore et al, 1996, Baladrón, 2010, Chimento & De Lucca, 2014 Bosque nativo Vega, 2001aVega, 2001aMartínez, 2001, Baladrón, 2010, Cardoni et al, 2011a, Isacch et al, 2014Bó et al, 2002Humedales Vega, 2001a, Stellatelli & Vega, 2010, Vega, 2011aVega, 2001a, Vega, 2011bCardoni et al, 2008, Bellagamba, 2011, Josens et al, 2012Bó et al, 2002, Vega, 2011c Dunas costeras Vega, 2001a, Vega, 2011a…”

Species-Area Relationships of Specialist Versus Opportunistic Pampas Grassland Birds Depend on the Surrounding Landscape Matrix

“…The habitat requirements of the grassland birds of the eastern Pampas are diverse (Isacch et al, 2014). They include specialist species that are only adapted to live in tall grasslands (e.g., Cistothorus platensis, Cranioleuca sulphurifera) (Isacch et al, 2004;Pretelli et al, 2013;Agra et al, 2015), generalist species that breed in tall grasslands but use many other habitats (e.g., Zonotrichia capensis, Poospiza nigrorufa), and species that use grasslands opportunistically as non-breeding habitat (e.g., Pitangus sulphuratus, Tyrannus melancholicus) (Filloy & Bellocq, 2007;Isacch & Cardoni, 2011;Codesido et al, 2012;Pretelli et al, 2013).…”