Opponents of wind generation say that wind turbines kill large numbers of birds, and they criticise climate activists for not being concerned about it. What is the truth of this?
I have gathered evidence in Birds and wind farms. Here is what I have learnt.
1. Wind farms do kill birds.
It’s a sad fact. Large birds, small birds, bats, sometime rare and endangered species.
2. Less birds die than is often claimed, but still more than we’d like.
Estimates range from 1 bird per turbine per year to 18. More recent figures seem to be lower.
3. Birds face much bigger problems than wind farms.
Cats, cars, buildings, power lines and hunting each cause hundreds of times more bird deaths than wind farms do. Those worried about bird deaths should logically be addressing some of these issues before worrying about wind farms.
4. Larger and rarer birds deserve special attention.
Large birds like eagles, hawks and vultures are often under greater pressure and need to be specially considered when developing new wind farms.
5. Bats can be worse affected than birds.
While bats are not as well thought of as birds, they are important parts of the ecology. They tend to be killed in larger numbers, and so merit additional consideration.
6. There are ways to significantly reduce the impacts of wind turbines on birds (and bats).
- Be careful to site turbines away from migratory paths, and feeding and breeding areas.
- Painting one blade black can make turbines far more visible to a bird and significantly reduce mortality.
- New sensing technology can detect a large bird approaching and slow or stop the turbine, making it less likely that birds will be damaged or killed.
- Emitting high frequency sounds can deter bats from coming near turbines.
The bottom line
The consequences of unchecked climate change are far worse than the killing of birds by turbines. Wind power is a significant source of renewable energy and must be utilised.
But with future development of wind farms informed by experience and new technology, there is every reason to expect that the number of bird deaths, especially rarer larger birds, can be greatly reduced.