A bat mortality study, supervised by University of Calgary biology professor Robert Barclay, has determined that the vast majority of bats found dead below wind turbines near Pincher Creek suffered severe injuries to their respiratory systems consistent with a sudden drop in air pressure – called barotrauma – that occurs when the animals get too close to the wind turbine blades.
The study shows that 90% of the bats examined after death showed signs of internal hemorrhaging consistent with barotraumas, while only about half showed evidence of direct contact with the blades.
The study was initiated by power generation company TransAlta Corp. after its wind farm operators noticed bat carcasses below wind turbines and approached Barclay, an internationally recognized bat expert, for advice.
‘It was important for us to determine as much as we could about this issue,’ says Jason Edworthy, director for stakeholder relations for TransAlta. ‘Ultimately, it's a situation we're working hard to alleviate. Ongoing research with the university is seeing some real results in terms of mitigation of collisions.’
The paper ‘Barotrauma Is A Significant Cause Of Bat Fatalities At Wind Turbines,’ by Erin F. Baerwald, Genevieve H. D'Amours, Brandon J. Klug and Robert M.R. Barclay, will be available online at current-biology.com.
SOURCE: University of Calgary