Among the many criticism that wind farms attract, some voices go against the stream. Apparently the giant turbines that sometimes dot the sea surface in many parts of Europe and beyond, attract al sort of wildlife, promoting the spontaneous building of reefs.

Crustaceans tend to thrive on their structures. This attracts fish, eager for food. Fish attract seals, and so on in a spiralling chain of fulfilled needs called "reef effect".

The discovery comes from the data collected on two such wind farms, Alpha Ventus off the German coast and Sheringham Shoal off the British coast. GPS technology can be used to track the movements of animals like seals and fish underwater. The data strongly suggest that the structures were used for foraging and the directed movements show that animals could effectively navigate to and between them. It is during the construction phase that wind farms are predicted to have the most dramatic negative effect on marine mammals, but once in place they offer also some unexpected advantages.