[mschuster91]

The species of birds that get killed are different. Wind turbines kill bigger birds, cats kill small songbirds.

Both are a non-negligible factor for their respective species.

[adgjlsfhk1]

Windmills generate more than 1% of power. Thus if you scale up the wind turbines by 100x (to cover more than all power generated over the world), they still kill over 100x fewer birds than cats.