Wind farms and abuse of statistics: bird edition

When "wind farms are dangerous" really just means "there are a lot of birds".

When dealing with large numbers, it helps to have an idea of the expected order of magnitude. That way, you can know whether it is merely the number which is large, or the thing it's describing as well.

For instance, if I tell you of a country with 140,000 people in long-term unemployment, it's rather important for you to know if I'm talking about the US (population 280 million) or Luxembourg (population 525,000).

That's a test a Spectator article, Wind farms vs wildlife, failed quite badly this week.

The author, Clive Hambler, is a lecturer in biological and human sciences at Oxford university, and quotes a number of statistics to demonstrate how dangerous wind farms are to wildlife. For instance:

Every year in Spain alone — according to research by the conservation group SEO/Birdlife — between 6 and 18 million birds and bats are killed by wind farms. They kill roughly twice as many bats as birds. This breaks down as approximately 110–330 birds per turbine per year and 200–670 bats per year. And these figures may be conservative if you compare them to statistics published in December 2002 by the California Energy Commission: ‘In a summary of avian impacts at wind turbines by Benner et al (1993) bird deaths per turbine per year were as high as 309 in Germany and 895 in Sweden.’

Similar claims are made throughout. Apparently the annual death toll of bats in the US and Canada is "up to three million", "Norwegian wind farms kill over ten white-tailed eagles per year", and so on.

What is missing is any context through which we can examine these numbers. It might change our interpretation of the figures to know that:

Domestic and feral cats have also been considered a major source of anthropogenic-caused mortality with estimates near 100 million annual bird deaths [in the US].

Or that, on roads near wetlands in Canada:

223 birds were killed per mile per year.                                                                                            

Power lines in the US are estimated to kill:

…approximately 130 million birds per year.                                                                                                        

While we're banning things, we may want to keep an eye out for that scourge of the avian world, windows:

97.6 to 976 million bird deaths per year in the U.S. due to collisions with windows… based on an estimated 1 to 10 bird deaths per structure per year from a fatality study in New York.

All those figures come from a 2005 paper by the US Department of Agriculture.

In other words, even with the massive figures from Spain – figures which show deaths per turbine per year two orders of magnitude higher than equivalent figures cited in the above paper, which are based on an assumption that for every confirmed death, there's nineteen uncomfirmed, and which come from a set of guidelines which explicitly concludes wind farms are OK for birds if built correctly (pdf) –  wind farms kill fewer birds than cats, power lines, roads or windows. That comparison would have been rather useful to include in the original piece. With that in mind, the numbers in the piece become less a demonstration of the awesome mortality of wind farms, and more a confirmation that yes, there are a lot of birds in the world.


It's been pointed out on Twitter that I'm not comparing like to like. Spain is smaller than the US, of course. Thankfully, the USDA also estimates the number of birds killed by wind farms in America: between 20,000 and 37,000 a year. I let you draw your own conclusions from the discrepancy.

Wind Turbines in Spain. Photograph: Wikimedia Commons

Alex Hern is a technology reporter for the Guardian. He was formerly staff writer at the New Statesman. You should follow Alex on Twitter.

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Let's seize our chance of a progressive alliance in Richmond - or we'll all be losers

Labour MPs have been brave to talk about standing aside. 

Earlier this week something quite remarkable happened. Three Labour MPs, from across the party’s political spectrum, came together to urge their party to consider not fielding a candidate in the Richmond Park by-election. In the face of a powerful central party machine, it was extremely brave of them to do what was, until very recently, almost unthinkable: suggest that people vote for a party that wasn’t their own.
Just after the piece from Lisa Nandy, Clive Lewis and Jonathan Reynolds was published, I headed down to the Richmond Park constituency to meet local Green members. It felt like a big moment – an opportunity to be part of something truly ground-breaking – and we had a healthy discussion about the options on the table. Rightly, the decision about whether to stand in elections is always down to local parties, and ultimately the sense from the local members present was that it would be difficult  not to field a candidate unless Labour did the same. Sadly, even as we spoke, the Labour party hierarchy was busily pouring cold water on the idea of working together to beat the Conservatives. The old politics dies hard - and it will not die unless and until all parties are prepared to balance local priorities with the bigger picture.
A pact of any kind would not simply be about some parties standing down or aside. It would be about us all, collectively, standing together and stepping forward in a united bid to be better than what is currently on offer. And it would be a chance to show that building trust now, not just banking it for the future, can cement a better deal for local residents. There could be reciprocal commitments for local elections, for example, creating further opportunities for progressive voices to come to the fore.
While we’ve been debating the merits of this progressive pact in public, the Conservatives and Ukip have, quietly, formed an alliance of their own around Zac Goldsmith. In this regressive alliance, the right is rallying around a candidate who voted to pull Britain out of Europe against the wishes of his constituency, a man who shocked many by running a divisive and nasty campaign to be mayor of London. There’s a sad irony in the fact it’s the voices of division that are proving so effective at advancing their shared goals, while proponents of co-operation cannot get off the starting line.
Leadership is as much about listening as anything else. What I heard on Wednesday was a local party that is passionate about talking to people and sharing what the Greens have to offer. They are proud members of our party for a reason – because they know we stand for something unique, and they have high hopes of winning local elections in the area.  No doubt the leaders of the other progressive parties are hearing the same.
Forming a progressive alliance would be the start of something big. At the core of any such agreement must be a commitment to electoral reform - and breaking open politics for good. No longer could parties choose to listen only to a handful of swing voters in key constituencies, to the exclusion of everyone else. Not many people enjoy talking about the voting system – for most, it’s boring – but as people increasingly clamour for more power in their hands, this could really have been a moment to seize.
Time is running out to select a genuine "unity" candidate through an open primary process. I admit that the most likely alternative - uniting behind a Liberal Democrat candidate in Richmond Park - doesn’t sit easily with me, especially after their role in the vindictive Coalition government.  But politics is about making difficult choices at the right moment, and this is one I wanted to actively explore, because the situation we’re in is just so dire. There is a difference between the Conservatives and the Lib Dems. Failing to realise that plays into the hands of Theresa May more than anyone else.
And, to be frank, I'm deeply worried. Just look at one very specific, very local issue and you’ll perhaps understand where I'm coming from. It’s the state of the NHS in Brighton and Hove – it’s a system that’s been so cut up by marketisation and so woefully underfunded that it’s at breaking point. Our hospital is in special measures, six GP surgeries have shut down and private firms have been operating ambulances without a license. Just imagine what that health service will look like in ten years, with a Conservative party still in charge after beating a divided left at another general election.
And then there is Brexit. We’re hurtling down a very dangerous road – which could see us out of the EU, with closed borders and an economy in tatters. It’s my belief that a vote for a non-Brexiteer in Richmond Park would be a hammer blow to Conservatives at a time when they’re trying to remould the country in their own image after a narrow win for the Leave side in the referendum.
The Green party will fight a passionate and organised campaign in Richmond Park – I was blown away by the commitment of members, and I know they’ll be hitting the ground running this weekend. On the ballot on 1 December there will only be one party saying no to new runways, rejecting nuclear weapons and nuclear power and proposing a radical overhaul of our politics and democracy. I’ll go to the constituency to campaign because we are a fundamentally unique party – saying things that others refuse to say – but I won’t pretend that I don’t wish we could have done things differently.

I believe that moments like this don’t come along very often – but they require the will of all parties involved to realise their potential. Ultimately, until other leaders of progressive parties face the electoral facts, we are all losers, no matter who wins in Richmond Park.


Caroline Lucas is the MP for Brighton Pavilion.