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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The problems with ending encryption to fight terrorism

Forcing tech firms to create a "backdoor" to access messages would be a gift to cyber-hackers.

The UK has endured its worst terrorist atrocity since 7 July 2005 and the threat level has been raised to "critical" for the first time in a decade. Though election campaigning has been suspended, the debate over potential new powers has already begun.

Today's Sun reports that the Conservatives will seek to force technology companies to hand over encrypted messages to the police and security services. The new Technical Capability Notices were proposed by Amber Rudd following the Westminster terrorist attack and a month-long consultation closed last week. A Tory minister told the Sun: "We will do this as soon as we can after the election, as long as we get back in. The level of threat clearly proves there is no more time to waste now. The social media companies have been laughing in our faces for too long."

Put that way, the plan sounds reasonable (orders would be approved by the home secretary and a senior judge). But there are irrefutable problems. Encryption means tech firms such as WhatsApp and Apple can't simply "hand over" suspect messages - they can't access them at all. The technology is designed precisely so that conversations are genuinely private (unless a suspect's device is obtained or hacked into). Were companies to create an encryption "backdoor", as the government proposes, they would also create new opportunities for criminals and cyberhackers (as in the case of the recent NHS attack).

Ian Levy, the technical director of the National Cyber Security, told the New Statesman's Will Dunn earlier this year: "Nobody in this organisation or our parent organisation will ever ask for a 'back door' in a large-scale encryption system, because it's dumb."

But there is a more profound problem: once created, a technology cannot be uninvented. Should large tech firms end encryption, terrorists will merely turn to other, lesser-known platforms. The only means of barring UK citizens from using the service would be a Chinese-style "great firewall", cutting Britain off from the rest of the internet. In 2015, before entering the cabinet, Brexit Secretary David Davis warned of ending encryption: "Such a move would have had devastating consequences for all financial transactions and online commerce, not to mention the security of all personal data. Its consequences for the City do not bear thinking about."

Labour's manifesto pledged to "provide our security agencies with the resources and the powers they need to protect our country and keep us all safe." But added: "We will also ensure that such powers do not weaken our individual rights or civil liberties". The Liberal Democrats have vowed to "oppose Conservative attempts to undermine encryption."

But with a large Conservative majority inevitable, according to polls, ministers will be confident of winning parliamentary support for the plan. Only a rebellion led by Davis-esque liberals is likely to stop them.

George Eaton is political editor of the New Statesman.

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