Wind turbine and birds death
But the population of the other eight species were restored once the windfarms were built. Windfarms may not affect all birds, but what if they affect birds of prey disproportionately? Large birds like hen harriers, eagles and vultures are also slower to reproduce than other species and so their populations are more likely to be affected by a small number of deaths. There are specific locations elsewhere in the world where windfarms have caused impressive-sounding numbers of fatalities amongst birds of prey.
In the Altamont Pass in California, for example, one study found about 4, wind turbines killed 67 golden eagles and 1, birds of prey in a year. In southern Spain , wind turbines located in an area used by many birds of prey and on the migratory path of many large birds killed a birds of prey in a year.
At another location in southern Spain turbines killed 30 griffin vultures and 12 common kestrels. What evidence is the RSPB relying on? There are studies to show that siting windfarms more sensitively can make a difference to how bird populations adapt to their new neighbours. In one frequently cited study, one windfarm in Spain created feeding sites away from turbines and shut down turbines at peak flight times.
Vulture deaths were reduced by 50 per cent for an electricity production loss of just 0. But the turbines were set back slightly — with the result that ultimately very few birds are killed. According to Birdlife International , with a thorough environmental assessment as part of the planning process, bird deaths can be significantly reduced.
In Scotland for example, planners use maps to identify high risk areas for protected birds. Some wind farms, such as the Penescal windfarm in Texas, use radar systems to detect flocks of birds and shut off the wind turbines as they approach.
Lots of human activities kill birds. Several studies have compared the effect of different energy sources on bird mortality overall. One, published earlier this year , calculates windfarms killed 20, birds died in in the US — while nuclear plants killed about , and fossil fueled power plants more than 14 million. US estimates published last year in a commentary piece in the journal Nature, although highly uncertain, also suggest the impact of wind turbine is far smaller than many other causes of bird death:.
Climate change is predicted to harm bird populations by affecting breeding or migration patterns , or altering their habitats. The few studies on windfarm siting are also encouraging, indicating that it can be used as an effective tool to reduce mortality.
Compared to other aspects of modern society, careful planning can lead to much-reduced mortality. This study found an average total of , total bird mortality due in the US due to wind turbines. Most notably, this study includes the mortality per MW, which breaks down how many birds die per MW of energy gained from the wind turbine.
The US total has a mean of 4. Although wind turbines may not be the number one killer of birds, and only 4. One highlighted example is at a single far near Altamont, CA where 75 golden eagles die each year due to the farm's turbines. It is difficult to effectively interpret the impact of wind turbines on bird mortality without comparing it to other energy sources. As seen by Fig.
According to the study, "The avian benefits of wind energy," fossil fuels are 17 times more dangerous to birds than wind turbines, and killed nearly 14 million birds in While wind turbines certainly contribute to bird mortality, they contribute to much less deaths than fossil fuels - a nonrenewable, unclean form of energy.
Wind turbines also kill the least number of birds per unit of energy compared to other types of energy. Additionally, efforts are being made to decrease the negative impact wind turbines have on bird mortalities through technological development and properly siting wind plants. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only.
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