Effects of fragmentation on biodiversity have received much attention in recent decades, as fragmentation can greatly reduce viable areas for living organisms. We studied its effect on Thamnophilus stictocephalus (Thamnophilidae), an understory bird, in semideciduous forest fragments in Alter-do-Chão, Santarém, Pará. We tested whether the density of Thamnophilus stictocephalus was a function of fragment size and shape, density of vegetation, or arthropod biomass. Density of Thamnophilus was positively related to fragment size, but not to the other factors analyzed. Arthropod biomass was positively related to fragment size. The density of T. stictocephalus in fragments was significantly higher than it was in continuous forest. Fragmentation processes had a pronounced effect on the relative density of T. stictocephalus.
fragmentation; forests; birds; Amazonia