Relation between Climate, Agricultural Land Cover and Bird Richness in a Mediterranean Natura 2000 Wetland

Abstract

In this study we explore for the first time the combined effect of climate variables and remote sensing land cover indicators on bird richness in a representative wetland location of the Thermaikos gulf Natura 2000 protected area in Northern Greece. In particular the association between bird diversity and climate, as well as remote sensed land cover indices was explored for seven successive seasons using correlation analysis and a Cox-Box transformed multivariate linear model. Three climate variables were tested, mean temperature, rain level and mean relative humidity and three land cover indices, the Normalized difference index (NDVI), the atmospheric resistance vegetation index (ARVI) and an agricultural band combination index (ABCI). Among the environmental drivers explored, temperature, rain levels and ABCI were significantly correlated to bird richness in contrast to NDVI and ARVI which showed a lower correlation, while relative humidity displayed the poorest correlation. Thus, temperature, rain levels and agricultural intensity significantly influenced bird composition. Additionally, the multivariable linear model indicates that temperature, rain levels and ABCI have a statistically significant effect (p<0.05) on bird species richness accounting for 73,02% of data variability. Based on the overall model results and the related 3D contour plot simulation we can conclude that in general, bird species richness increases with an increase in temperature and Rain, as well as with a decrease in agricultural intensity (ABCI). Understanding the factors that can affect bird biodiversity of species is of great importance in ecosystem management and species conservation.