A few figures from North America:
  • Wind turbines kill between 214,000 and 368,000 birds each year. 
  • Up to 6.8 million bird deaths are attributed to collisions with cell and radio towers.
  • Feral and domestic cats are estimated to kill 1.4 billion to 3.7 billion birds each year. (By far the worst!)
This makes the wind turbines positively 'bird friendly'.