Most of the species that reside in trees start traveling towards the south for winter due to lack of insects. But that’s not the case of a Pacific Northwest bat. As per research by the Oregon State University-Cascades, those bats have danger from wind farms. The study notes the hoary bats could have an insecure future as its counts have decreased by 2% every year. Those bats do not remain inactive or sleep during the winter season and prefer migrating to the south. During their journey from North America to South America, they often face many difficulties.
As per Tom Rodhouse, study’s author, wind turbines are liable for the massive fall in the number of bats. Notably, there is a rise in the windmills on commercial wind energy plants has become a trend in Oregon and Washington state. Both states together host more than 3,500 wind turbines which provide up to 6,300MW of energy. Even more, both states have assembled the most of the wind parks near east of The Dalles, the Columbia River Gorge. Other plants in the area are located near Baker City in Oregon along with Walla Walla and Ellensburg in Washington. The study highlights the collision of bats with propellers on the windmills results in the death of bats.
Tom noted another aspect that hoary bats face while migration, is barotrauma. It means an injury caused due to increased pressure of air or water. On the other hand, the rotating blades of a windmill result in low-pressure zones, and ultimately Barotrauma. When bats fly over these regions, it harms bats. This instant change in air pressure gives rise to lung expansion of bats. Even more, the speed of enlargement is much higher than the bats can breathe out. As a result, bat’s vessels burst. Tom said this explosion fills their little lungs with blood. Both, barotrauma and direct collision, have led in death of millions of bats in the past twenty years. Authors of the study surmise concern that if the trend remains the same, bats are at extinction risk. They have published outcomes of the research in Ecology and Evolution.