Global environmental challenges
By my count there are at least two dozen dead white storks in this photo taken in Saudi Arabia after they flew into the power lines — part of a wider problem in which millions of birds die every year by flying into obstacles put up by people.
This weekend, May 9-10, thousands of people around the world are marking a U.N.-backed “Migratory Bird Day” (yes, it’s a long day) with a theme about “Barriers to Migration” — such as buildings, wind turbines, power lines and fences.
It’s easy to see how birds might fly by accident into thin wires like those above south of Jeddah but harder to understand why they slam into enormous buildings — some, apparently, may be flying towards what they think is the safety of a tree and end up crashing into a window in which the tree is reflected.
And the blades of wind turbines spin at up to 200 km (125 miles) per hour, making them all but invisible.
Migratory birds have an amazing ability to grow muscles before their flights by eating a lot but without hard training. Imagine being able to copy that — get in shape by lounging on the sofa gorging yourself for weeks and then run a marathon.
But there are signs that birds will be in trouble in future because climate change will shift their breeding grounds further north in Europe, according to a study of European warblers today. (for a story, click here) Wintering grounds in Africa or southern Europe are unlikely to move so much.