Wind turbine power and land cover effects on cumulative bat deaths.

Wind turbines (WT) cause bird and bat mortalities which depend on the WT and landscape features. The effects of WT features and environmental variables at different spatial scales associated to bat deaths in a mountainous and forested area in Thrace, NE Greece were investigated. Initially, we sought to quantify the most lethal WT characteristic between tower height, rotor diameter and power. The scale of interaction distance between bat deaths and the land cover characteristics surrounding the WTs was quantified. A statistical model was trained and validated against bat deaths and WT, land cover, and topography features. Variance partitioning between bat deaths and the explanatory covariates was conducted. The trained model was used to predict bat deaths attributed to existing and future wind farm development in the region. Results indicated that the optimal interaction distance between WT and surrounding land cover was 5 km, the larger distance than the ones examined. WT power, natural land cover type and distance from water explained 40 %, 15 % and 11 % respectively of the total variance in bat deaths by WTs. The model predicted that operating but not surveyed WTs comprise of 377.8 % and licensed but not operating yet will contribute to 210.2 % additional deaths than the ones recorded. Results indicate that among all WT features and land cover characteristics, wind turbine power is the most significant factor associated to bat deaths. In addition, WTs located within 5 km buffer comprised of natural land cover types have substantial higher deaths. More WT power will result in more deaths. Wind turbines should not be licensed in areas where natural land cover at a radius of 5 km exceeds 50 %. These results are discussed in the climate-land use-biodiversity-energy nexus.

Sacred oak woods increase bird diversity and specialization: Links with the European Biodiversity Strategy for 2030.

Sacred groves in Greece are usually forest remnants with large trees around chapels, protected through centuries by Orthodox religion. We examined the comparative ecological value of 20 oak-dominated sacred groves vs managed oakwoods, in terms of their habitat characteristics and avian communities (passerines and woodpeckers). Sacred groves have maintained a more pronounced old-growth character than managed oakwoods in terms of average Diameter at Breast Height (DBH) and tree height. Besides holding significantly greater bird species richness and abundance, they supported greater functional richness, phylogenetic diversity, and phylogenetic bird species variability. Bird communities in sacred groves were more heterogeneous and showed greater avian specialization levels than in managed woods. Generalized Linear Models showed that the main factor positively affecting all aspects of bird diversity was DBH, while the abundance of dead trees increased bird abundance. Our results underline the importance of maintaining large-sized trees in forest management practices to support bird diversity and decrease biotic homogenization. Since the new European Biodiversity Strategy explicitly requires all remaining European primary and old-growth forests to be strictly protected by 2030, we argue that sacred groves, despite their small size, meet the criteria to be considered in the strict protection and restoration targets of the strategy, as primary old growth woods of high biodiversity value.