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.

Update

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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How the Lib Dems learned to love all-women shortlists

Yes, the sitting Lib Dem MPs are mostly white, middle-aged middle class men. But the party's not taking any chances. 

I can’t tell you who’ll be the Lib Dem candidate in Southport on 8 June, but I do know one thing about them. As they’re replacing a sitting Lib Dem (John Pugh is retiring) - they’ll be female.

The same is true in many of our top 20 target seats, including places like Lewes (Kelly-Marie Blundell), Yeovil (Daisy Benson), Thornbury and Yate (Clare Young), and Sutton and Cheam (Amna Ahmad). There was air punching in Lib Dem offices all over the country on Tuesday when it was announced Jo Swinson was standing again in East Dunbartonshire.

And while every current Lib Dem constituency MP will get showered with love and attention in the campaign, one will get rather more attention than most - it’s no coincidence that Tim Farron’s first stop of the campaign was in Richmond Park, standing side by side with Sarah Olney.

How so?

Because the party membership took a long look at itself after the 2015 election - and a rather longer look at the eight white, middle-aged middle class men (sorry chaps) who now formed the Parliamentary party and said - "we’ve really got to sort this out".

And so after decades of prevarication, we put a policy in place to deliberately increase the diversity of candidates.

Quietly, over the last two years, the Liberal Democrats have been putting candidates into place in key target constituencies . There were more than 300 in total before this week’s general election call, and many of them have been there for a year or more. And they’ve been selected under new procedures adopted at Lib Dem Spring Conference in 2016, designed to deliberately promote the diversity of candidates in winnable seats

This includes mandating all-women shortlists when selecting candidates who are replacing sitting MPs, similar rules in our strongest electoral regions. In our top 10 per cent of constituencies, there is a requirement that at least two candidates are shortlisted from underrepresented groups on every list. We became the first party to reserve spaces on the shortlists of winnable seats for underrepresented candidates including women, BAME, LGBT+ and disabled candidates

It’s not going to be perfect - the hugely welcome return of Lib Dem grandees like Vince Cable, Ed Davey and Julian Huppert to their old stomping grounds will strengthen the party but not our gender imbalance. But excluding those former MPs coming back to the fray, every top 20 target constituency bar one has to date selected a female candidate.

Equality (together with liberty and community) is one of the three key values framed in the preamble to the Lib Dem constitution. It’s a relief that after this election, the Liberal Democratic party in the Commons will reflect that aspiration rather better than it has done in the past.

Richard Morris blogs at A View From Ham Common, which was named Best New Blog at the 2011 Lib Dem Conference

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