2008/03/01 by Hari Sridhar, K. Sankar · 1 citation
Environmental Science · Agricultural and Biological Sciences · #Ecology and Vegetation Dynamics Studies #Plant and animal studies #Species Distribution and Climate Change #Flock #Habitat #Ecology #Biology
paper · doi:10.1017/s0266467408004823
openalex publication_date 2008/03/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/05/21
Abstract: Habitat degradation affects mixed-species bird flocks (flock hereafter) through two mechanisms – changes in the bird community from which flocks are drawn and changes in the propensities of species to flock. We determined the relative influence of these two mechanisms by examining variation in flocks across nine rain-forest fragments (range 11–2600 ha) in a plantation landscape in the Western Ghats, India. We found differences between fragments in average number of species (range 10.8–15.2) and individuals (range 19.0–37.6) per flock, number of species that participated in flocks (range 34–59), encounter rates (range 0.5–2.4 flocks h −1 ) and flock composition. Multiple regression and randomization tests revealed that different mechanisms contributed to this variation. Three flock variables (open-forest individuals per flock, total open-forest species that participated in flocks in a fragment, flock composition) mainly reflected changes in the bird communities of fragments. Habitat structure strongly influenced three flock variables (open-forest species per flock, total and rain-forest individuals per flock) and flock composition to a lesser extent. Finally, flock encounter rate was strongly related to fragment area, but not to abundance of flock participants indicating habitat degradation-induced changes in propensities of species to flock.