I’m a keen bird watcher and so am interested in the impact of wind farms on bird life. I asked Acciona for statistics on the number of bird fatalities at Waubra and got the following response:
ACCIONA implements a comprehensive bird monitoring program at the Waubra Wind Farm in accordance with Avifauna Management Plan which was approved by the Minister for Planning in October 2006. This Plan was supported by extensive bird surveys of the site prior to commissioning of the wind farm.
The first year of bird mortality searches at the Waubra Wind Farm were completed in 2010. Dead bird searches are done by two highly trained German Short-haired Pointers and their handler. It is a unique survey method that allows a search of large areas of the wind farm to be done in an efficient and cost-effective manner. The dogs have also proven to have a higher searcher efficiency than people.
There were 28 birds found during the first year of mortality searches. No nationally or state threatened species were impacted. Magpies accounted for 43% of all bird collisions.
The extrapolated results for the entire wind farm indicate that 1.65 birds are killed per turbine annually. This can also be presented as 1.1 birds/MW/year.
The mortality rates when compared to wind farms overseas suggest that impacts at Waubra are relatively low. An investigation of 19 wind energy facilities in the USA showed an average rate of 3 birds/MW/year.
I did some hunting around on other threats to bird life, and found by way of comparison, a study of feral cats on Macquarie Island which estimated that each cat would kill around 150 rabbits and 150 sea birds per year (Queensland Department of Primary Industries, Feral Cat Ecology and Control, 2010).
So if my maths is correct, it seems in one year two feral cats may well kill more critters than the whole of the Southern Hemisphere’s largest wind farm.