PERTH, June 25 -- A conservation group has warned that the giant wind turbines are proving a hazard to birds especially for the endangered species.

Though wind energy is considered a clean and environment-friendly form of energy, the giant turbine blades are killing critically-endangered birds' species.

Critically-endangered species are among those being killed, BirdLife Tasmania spokesman Eric Woehler said on Tuesday.

"The blade is sometimes approaching 300 kilometres per hour, so the birds don't recognise that as a threat and don't change their behaviour around them," Dr Woehler said.

"We're building all of these things, and we need to have renewable energy - but it has to be done in such a way to not make things worse for criticall...