Habitat and landscape factors associated with neotropical waterbird occurrence and richness in wetland fragments

Abstract

Habitat destruction alters the structure and spatial arrangement of remnants and creates a novel matrix, affecting the structure of biological communities. This study evaluated the contribution of patch, class and landscape level attributes of 42 wetland fragments and surrounding landscapes on the richness, abundance and presence of waterbird species. Twelve monthly censuses identified 55 species--ranging from 3 to 40 among fragments, and a total of 84,286 birds--ranging from 15 to 19,322. Wetland areas varied from 0.2 ha to 145.2 ha. The presence of 37 out of 42 species could be predicted from the structure of the fragments and the landscapes. The most important predictors were the wetland area (22 models), the rice field matrix permeability (13 models), the microhabitat richness (7 models), the wetland connectivity (5 models), and the wetland isolation (5 models). Discriminant analysis showed that fragments richer in species than expected from their areas, are found in landscapes with greater connectivity and matrix permeability than the species-poor fragments. The total area of rice fields was not related to the richness, abundance or presence of waterbirds in the wetlands fragments. The results suggest that the maintenance of the connectivity among fragments and the matrix permeability through rice-fields could be managed to foster the waterbird conservation at the landscape scale.

Agricultural ponds as alternative habitat for waterbirds: spatial and temporal patterns of abundance and management strategies

“…This program enables partial analyses, where the influence of particular variables (termed covariables) is eliminated before the influence of the variables of interest (termed environmental variables) is tested. CA is a descriptive/exploratory technique designed to analyse multiway tables containing some measure of correspondence between the rows and columns (Greenacre 1984;Legendre and Legendre 1998). CA attribute scores to both species guilds and environmental variables so that the correlation between environmental variables scores and species scores is maximal, given the best 'correspondence' between species and variables (Prodon 1992).…”

Differing responses to landscape change: implications for small mammal assemblages in forest fragments

“…Debuse et al 2007;Guadagnin and Maltchik 2007;Luther et al 2008). Here, we have shown that, even when the number of species is small, a variety of parameters operating at different scales can be important.…”

Determinants of species-area relationships for marsh-nesting birds

“…Such relationships have been reported for marsh bird communities (Burger et al 1982, Brown and Dinsmore 1986, Craig and Beal 1992, Colwell and Taft 2000, Shriver et al 2004 Corresponding author. Email: mail@ birdconservationresearch.org Guadagnin and Maltchik 2007), but the factors contributing to them remain unclear.…”

“…Potential habitat effects on richness include increasing heterogeneity that permits more marsh species to be present because they require either specific or multiple habitats (Weller 1999, Lor and Malecki 2006, Guadagnin and Maltchik 2007. One habitat feature, water level, is frequently cited as a determinant of the presence of certain species (Weller 1999, DesGranges et al 2006.…”