Griffon vulture mortality at wind farms in southern Spain: Distribution of fatalities and active mitigation measures

Abstract

a b s t r a c tWind is increasingly being used as a renewable energy source around the world. Avian mortality is one of the negative impacts of wind energy and a new technique that reduces avian collision rates is necessary. Using the most frequently-killed species, the griffon vulture (Gyps fulvus), we studied its mortality at 13 wind farms in Tarifa, Cadiz, Spain, before (2006-2007 and after (2008)(2009)) when selective turbine stopping programs were implemented as a mitigation measure. Ten wind farms (total of 244 turbines) were selectively stopped and three wind farms (total of 52 turbines) were not. We found 221 dead griffon vultures during the entire study and the mortality rate was statistically different per turbine and year among wind farms. During 2006During -2007 griffon vultures were found dead and the spatial distribution of mortality was not uniformly distributed among turbines, with very few turbines showing the highest mortality rates. The 10 most dangerous turbines were distributed among six different wind farms. Most of the mortalities were concentrated in October and November matching the migratory period. During 2008-2009, we used a selective stopping program to stop turbines when vultures were observed near them and the griffon vulture mortality rate was reduced by 50% with a consequent reduction in total energy production of by the wind farms by only 0.07% per year. Our results indicate that the use of selective stopping techniques at turbines with the highest mortality rates can help to mitigate the impacts of wind farms on birds with a minimal affect on energy production.

Flight Paths of Migrating Golden Eagles and the Risk Associated with Wind Energy Development in the Rocky Mountains

“…Both the predictability of conditions that will increase passage rates, i.e., time of day, increasing wind speed, and temperature, as well as conditions that alter routes within installation sites that increase ridge-top crossings, i.e., seasonality and low wind speed, could allow for mitigation strategies to reduce eagle collisions in postconstruction. For example, de Lucas et al (2012) report on programs in Spain where visual observers monitor risk-sensitive flight patterns of migrating Griffon Vultures (Gyps fulvus) and use this information to temporarily idle individual turbines where high movement patterns are being observed. Such techniques have led to a 50% reduction in the detected rate of vulture collisions at an estimated loss of less than 0.1% in power generation per year.…”

Raptor Interactions With Wind Energy: Case Studies From Around the World

“…The use of field observers to monitor bird activity close to wind farms has been used in several countries (STRIX 2013;de Lucas et al 2012;May et al 2010). This has included observations specifically aimed at informing turbine shutdown during periods of high collision risk, such as during periods of high display activity of wedge-tailed eagles Aquila audax and foraging orange-bellied parrots Neophema chrysogaster in Australia (Symons Ed.…”

“…This has included observations specifically aimed at informing turbine shutdown during periods of high collision risk, such as during periods of high display activity of wedge-tailed eagles Aquila audax and foraging orange-bellied parrots Neophema chrysogaster in Australia (Symons Ed. 2010) as well as in relation to griffon vultures Gyps fulvus in Spain (de Lucas et al 2012) and to white-tailed eagle Haliaeetus albicilla activity at a wind farm in Norway (May et al 2010).…”

“…De Lucas et al (2012) studied griffon vulture mortality at a total of 13 wind farms in southern Spain. Initially, regular and frequent mortality searches were used in combination with field observations to identify conditions and ecological factors related to increased collision risk.…”

“…Shutdown-on-demand has previously been shown to be effective in reducing mortality in a large soaring species while maintaining a low loss in energy output (de Lucas et al 2012).…”