The influence of fire on the assemblage structure of foraging birds in grasslands of the Serra da Canastra National Park, Brazil

Abstract

Grasslands are the most threatened physiognomies of the Cerrado biome (Brazilian savanna), a biodiversity hotspot with conservation as a priority. The Serra da Canastra National Park protects the most important remnants of the Cerrado's southern grasslands, which are under strong anthropogenic pressure. The present study describes the structure of bird assemblages that directly use food resources in burned areas, comparing areas affected by natural fi re to the areas where controlled fi res were set (a management strategy to combat arson). The tested null hypothesis was that different bird assemblages are structured in a similar manner, regardless of the post-fi re period or assessed area. Between December/2012 and January/2015, 92 species were recorded foraging in the study areas. The results indicate that both types of burnings triggered profound and immediate changes in bird assemblages, increasing the number of species and individuals. Natural fi res exhibited a more signifi cant infl uence on the structure (diversity and dominance) than prescribed burnings. Nevertheless, all the differences were no longer noticeable after a relatively short time interval of 2-3 months after prescribed burnings and 3-4 after natural fi res. The fi ndings may help the understanding of prescribed burnings as a management strategy for bird conservation in grasslands.

Prescribed fire enhances seed removal by ants in a Neotropical savanna

“…Increased seed removal by ants after fire agrees with results from similar studies in Australian savannas, and is likely due to enhanced foraging effort by ant colonies after fire (Parr et al, 2007). Fire seems to affect the bird communities most in short term in Cerrado, with some savanna specialist taxa and birds of prey probably benefiting from fire (Reis et al, 2016). Although some rodents may find refuges in burrows and nearby vegetation not affected by fire and recolonize burned sites (Puig-Gironès et al, 2018), it is likely that rodents foraging for seeds decrease in burned sites due to temporal reductions in rodent populations and increasing foraging for invertebrates (Vieira & Briani, 2013).…”

No Net Loss of Species Diversity After Prescribed Fires in the Brazilian Savanna

“…Although changes in vegetation structure represent modifications in habitat for plants and animals, fire-driven changes in plant communities of tropical savannas due to fire are much more about structure than species composition or biodiversity (Higgins et al, 2007;van Wilgen et al, 2007;Lebbink et al, 2018), since fire does not eliminate typical savanna species. No biodiversity losses due to fire have been consistently observed in savannas for most animal groups, such as arthropods (but see Morais and Benson, 1988;Andersen and Müller, 2000;Maravalhas and Vasconcelos, 2014;Vasconcelos et al, 2017), birds (Cavalcanti and Alves, 1997;Corbett et al, 2003;Mills, 2004;Reis et al, 2016), mammals (Vieira, 1999;Prada and Marinho-Filho, 2004;Beale et al, 2018), reptiles (Griffiths and Christian, 1996;Corbett et al, 2003;Langford et al, 2007;Morais et al, 2011;Costa et al, 2013), and amphibians (Corbett et al, 2003;Langford et al, 2007;Morais et al, 2011). Despite the pattern of low impact on richness observed in most studies, however, there are some exceptions when fire effects are analyzed at a small scale, comparing different pieces of the vegetation mosaic.…”

Temporal changes in bird communities in areas with different histories of fire disturbance in highland grasslands of Brazil

“…In grasslands of the Serra da Canastra National Park, southeastern Brazil, burnings triggered profound and immediate changes in bird assemblages, increasing the number of species and individuals right after the fire [35]. Bahía and Zalba [32] found that the abundance and richness of birds were lower one year after a burn and increased significantly two years afterward.…”

“…In South America most of the studies about fire effects on birds in non-forest habitats have been conducted in Argentina (e.g., [29][30][31][32]) or in Central Brazil (e.g., [33][34][35][36]). Few studies have specifically assessed this issue in southern Brazilian highland grasslands, and most have only compared burned and unburned areas (e.g., [37][38][39]).…”