Species richness and relative abundance of birds in natural and anthropogenic fragments of Brazilian Atlantic forest

Abstract

Bird communities were studied in two types of fragmented habitat of Atlantic forest in the State of Paraná, southern Brazil; one consisted of forest fragments that were created as a result of human activities (forest remnants), the other consisted of a set of naturally occurring forest fragments (forest patches). Using quantitative data obtained by the point counts method in 3 forest patches and 3 forest remnants during one year, species richness and relative abundance were compared in those habitats, considering species groups according to their general feeding habits. Insectivores, omnivores, and frugivores presented similar general tendencies in both habitats (decrease of species number with decreasing size and increasing isolation of forest fragment). However, these tendencies were different, when considering the relative abundance data: the trunk insectivores presented the highest value in the smallest patch while the lowest relative abundance was in the smallest remnant. In the naturally fragmented landscape, time permitted that the loss of some species of trunk insectivores be compensated for the increase in abundance of other species. In contrast, the remnants essentially represented newly formed islands that are not yet at equilibrium and where future species losses would make them similar to the patches.

Evaluating the effects of habitats on birds in the walnut fruit forests: a case study from Kyrgyzstan

“…Similar findings have been presented in various case studies examining these two different habitat types in countries around the world (e.g. Anjos 2004;Augenfeld, Franklin, and Snyder 2008;Martin and Blackburn 2010). From a silvicultural perspective, the SF plots are over-matured with homogenous walnut tree stands; natural regeneration was rarely seen due to the high level of human impact, which means that the future development of these habitats is not yet secure.…”

“…Research studies investigating bird habitats (Sekercioglu 2002;Simon, Schwab, and Otto 2002;Anjos 2004;Naidoo 2004;Uezu, Metzger, and Vielliard 2005;Round, Gala, and Brockelman 2006) have shown that bird species richness and abundance are strongly dependent on the vertical and horizontal heterogeneity of habitats, and that these two parameters can be good indicators with which to assess structural changes occurring within forests. In terms of the results presented here, although no strongly significant relationship between vegetation variables and bird diversity was observed, a considerable dependence can be seen between selected indicator bird species and certain forest flora parameters.…”

“…However, a number of indicators have been proposed with which to assess SFM -including its influence on biodiversity -at different levels (Bond 1994;Schuck et al 1994;Stork et al 1997;Ferris and Humphrey 1999;Noss 1999;Lindenmayer, Margules, and Botkin 2000;Lindenmayer and Franklin 2002;Loehle et al 2005). Of these proposed indicators, 'bird communities' have often been chosen and used by many researchers since they represent a high level of ecological uniformity and flexibility in terms of habitat change (Furness, Greenwood, and Jarvis 1993;Howard et al 1998;Simon, Schwab, and Otto 2002;Anjos 2004;Watson, Whittaker, and Dawson 2004;Diaz et al 2005;Loss, Ruiz, and Brawn 2009;Gil-Tena, Brotons, and Saura 2010;Sheldon, Styring, and Hosner 2010).…”

Effects of Connectivity on the Forest Bird Communities of Adjacent Fragmented Landscapes

“…A previous study, also carried out in the state of Paraná, showed that naturally fragmented landscapes do not necessarily have higher connectivity (Anjos, 2004). This study shows that, in comparison to a humanfragmented landscape, the bird community in a naturally fragmented landscape is not strongly influenced by connectivity.…”

Evaluating the ecological integrity of Atlantic forest remnants by using rapid ecological assessment

“…PEMG comprises approximately 650 ha and is considered the best conserved SAF remnant in the region. The area has high biological integrity (Silveira 2006;Anjos 2004) and was designated a high priority site for biodiversity conservation by a Brazilian Ministry of Environment panel of specialists (MMA 2002).…”