The role of climate and environmental variables in structuring bird assemblages in the Seasonally Dry Tropical Forests (SDTFs)

Abstract

Understanding the processes that influence species diversity is still a challenge in ecological studies. However, there are two main theories to discuss this topic, the niche theory and the neutral theory. Our objective was to understand the importance of environmental and spatial processes in structuring bird communities within the hydrological seasons in dry forest areas in northeastern Brazil. The study was conducted in two National Parks, the Serra da Capivara and Serra das Confusões National Parks, where 36 areas were sampled in different seasons (dry, dry/rainy transition, rainy, rainy/dry transition), in 2012 and 2013. We found with our results that bird species richness is higher in the rainy season and lower during the dry season, indicating a strong influence of seasonality, a pattern also found for environmental heterogeneity. Richness was explained by local environmental factors, while species composition was explained by environmental and spatial factors. The environmental factors were more important in explaining variations in composition. Climate change predictions have currently pointed out frequent drought events and a rise in global temperature by 2050, which would lead to changes in species behavior and to increasing desertification in some regions, including the Caatinga. In addition, the high deforestation rates and the low level of representativeness of the Caatinga in the conservation units negatively affects bird communities. This scenario has demonstrated how climatic factors affect individuals, and, therefore, should be the starting point for conservation initiatives to be developed in xeric environments.

Local extinctions exceed colonization rates in a bird community during dry years in the Brazilian Caatinga

“…The vertical bars are standard errors northeastern Brazil, highlighting the importance of landscape heterogeneity as a mechanism shaping bird communities in the Caatinga (Santos 2004;Araujo et al 2012;Gonçalves et al 2017). Landscape heterogeneity is one of the main sources of variation in bird diversity (Heezik and Seddon 1999;Gillespie and Walter 2001;Smith 2015) and its influence is not limited to arid and semiarid environments, or extreme climatic events (Wiens 1989). Despite the limited number of habitat replicates surveyed in the present study, it is possible that the differences in species richness between plots resulted, at least partly, from the drought conditions that dominated the study period, in particular, in 2012.…”

Predicting the Impact of Climate Change on the Future Distribution of Paederus fuscipes Curtis, 1826, in China Based on the MaxEnt Model

“…This may be one of the reasons why the suitability area of P. fuscipes is significantly reduced in future predictions [ 39 , 40 ]. Humidity, solar radiation, and air temperature affect the metabolic rates of animals and plants in tropical forests [ 41 ]. Previous studies have also shown that P. fuscipes prefers to overwinter in crop fields with dense vegetation cover that is relatively sheltered from the wind and cold.…”

Local species turnover increases regional bird diversity in mangroves

“…2016; Gonçalves et al . 2017; Bhakti et al . 2018) in which either environmental gradients, habitat structure, or both, were important drivers of the composition of the local bird metacommunity and supported a process of species sorting (Leibold et al .…”