Monday, July 24, 2017

Issues with bat/wind turbine study, worse reporting, and awful Op-Editing

(Maybe worth emphasizing this is Brian writing, not Eli or John.)

A new study gives some reason to believe that wind turbines have secondary effects on bat mortality compared to other anthropogenic factors like intentional killing, accidents, and the imported fungal disease called White Nose Syndrome. You'd have trouble knowing that though after reading the bad reporting in Scientific American and worse Op-Editing by a Manhattan Institute 'scholar'. To be fair to the secondary reports, the study itself could've done a better job discussing its results.

Disclaimer time! I'm not a scientist, let a alone a bat specialist, maybe I'm off. Regardless, said specialists probably will get something useful from the study, but it's broader public effect isn't so great.

So, problems with the study:

1. It is not a study of bat mortality. It's a study of Mass Mortality Events (ten bodies or more). If you don't know the relationship between MMEs and overall mortality (and apparently we don't), then you don't know the importance of MME causes to bat conservation. Aside from one throwaway sentence (that many bat species are gregarious and therefore likely to have MMEs) this issue isn't discussed. There's also no discussion of habitat destruction except when the destruction creates MMEs, when habitat destruction is likely far more important than any other factor.

2. Actually, it's not a study of MMEs, it's a study of reported MMEs. In other words, nobody went out and did transects in places with bats to survey for MMEs - this study just looks at reports of MMEs however they came to be, creating a significant bias because what gets reported is not even an attempt at a random survey of MMEs. This is not well-acknowledged in the study, with an important exception saying wind turbine reports are biased higher because of mandatory reporting requirements that don't exist for other causes. Subsequent reporting on this study by others omits this disclaimer.

3. Worst of all IMHO is they included qualitative reports of MMEs (i.e. reports of "many" dead bats) and they did not adjust measured mortality quantitatively for the number of deaths in each MME. So a MME of 10 bats counts equally in their study with one killing 10,000 bats (and they acknowledge some MMEs at that level and higher). I think this is worst of all because it seems like something they could actually fix, while the first two problems are limitations they couldn't fix but could have acknowledged more readily.

Related to this last flaw of what MMEs were considered is that they excluded MME reports of food markets and of bat imports. My cynical take is they excluded those categories because they'd overwhelm the others and highlight the problem of selection bias for reported MMEs. They say they excluded food market reports because it's been studied elsewhere, an explanation that doesn't make sense when surveying relative causes of mortality.

Disclaimer time again! I didn't read the supplements which might give some defense against my criticism, but they weren't attached to the Google Scholar link. I supposed I could've been more industrious and contacted the authors, but I also think these flaws should've been addressed in the study itself.

Anyway, some props to the study for disclosing its limitations even if they could've highlighted them and done things differently. Below are the key category results IMO - they disclose and then ignore the figures in parentheses, we will do the opposite (and note the study includes other categories that aren't relevant to this post):

Category                          Total MMEs (and order of magnitude for maximum number carcasses in single events per category)

Intentional killing           205 (10x5)
Accidental                         66 (10x4)
Wind turbines                  281 (10x2)
White Nose Syndrome   266 (10x4)

What I take from this is that of these four categories, wind turbines kill the fewest bats - by two or more orders of magnitude. Contrast this with the study abstract that says

 Collisions with wind turbines and white-nose syndrome are now the leading causes of reported MMEs in bats.

Scientific American takes that to mean

wind turbines are, by far, the largest cause of mass bat mortality around the world

And Robert Bryce of the Manhattan Institute:

wind turbines are now the largest cause of mass bat mortality. 

People who don't read the original study (Bryce doesn't even link to it) are unlikely to catch the importance of the qualifier "mass," or that they're measuring events and not the numbers of bats killed in mass events. Even with all that, Scientific American's "by far" is completely wrong. Bryce gets many other things wrong or exaggerated in his anti-wind jeremiad.

One wrinkle to this is that the study shows a large change in MMEs since 2000, with far fewer of other categories while nearly-identical, large numbers of MMEs occur from wind turbines and White Nose Syndrome (maybe 37% of events from turbines and 36% from WNS). That still doesn't change the fact that WNS kills bats by two orders of magnitude more, nor that there's a reporting bias to show more wind turbine MMEs.

I'm not rejecting that turbines killing bats are a concern (my idea btw is to put high-frequency, very short distance sonar warning noisemakers on problematic turbines), just how it's being discussed. The study does mention climate change as a future and present-day impact on bats. Bryce somehow omits that.

What this all needs is perspective.

20 comments:

David B Benson said...

Wind turbines cause bat and bird mortality. For bats this is easy. Don't run the turbines during bat hunting hours in bat territory. This will have little effect on wind turbine profitability.

jch1952 said...

When I read those news reports I thought I smelled a bat. Thanks for writing this.

Mark said...

I read somewhere (perhaps in Science) that there is a difference in numbers of killed between local bats and migrating bats. Also, it appears European bats may have developed more resistance to White Nose Syndrome (think I saw that in National Speleological Society News).

Tom Gray said...

OK, so... I know a lot about this issue, although some of my knowledge is out of date (probably not much, though, as the basics don't seem to be changing). (I was a member of the governing board of the Bats and Wind Energy Cooperative for several years in the '00s, as a rep of the American Wind Energy Association, for which I was Director of Communications.)

Some comments:

- As suggested in the comments, Robert Bryce's credibility is zero. He's been lying about wind power (MHO) for 15 years or so, as a hack for the Manhattan Institute, which was founded by the Koch brothers and is relentlessly anti-clean-energy.

- Wind's bat problem is definitely a real one, accentuated by 1) the fact that bats can and do avoid other sources of mortality that affect birds--the outstanding example being buildings; and 2) the fact that bats have smaller numbers of offspring, so that any source of mortality is magnified in comparison.

- That said, again as your post indicates, we don't know jack about bat mortality from many sources, including cats (I know there is some, because a few years ago, our cat killed one that was in the house) or automobiles. Very little systematic research has been conducted, so the only thing that can be said with certainty is that wind's impact, among anthropogenic sources, is significant.

- "Don't run the turbines during bat hunting hours in bat territory. This will have little effect on wind turbine profitability." Hmmm. Well, sort of. The bats that collide with turbines are mostly solitary, migratory, tree-roosting bats (hoary bats, Eastern red bats, silver-haired bats), not cave dwellers like little browns. Shutting turbines down for extended periods would definitely cut into revenues. However, my impression is that it's true that changing turbine operating algorithms so that turbines start up at higher wind speeds (bat activity declines as wind speeds increase) is a relatively inexpensive way to reduce bat mortality. Industry has made some steps in this direction.

- "I read somewhere (perhaps in Science) that there is a difference in numbers of killed between local bats and migrating bats." Definitely true, because they're different species. (I personally suspect what's going on is that bats haven't adapted to wind turbines because there's really nothing in nature like them--bats, especially bats that roost in trees, may be curious about what at first look like enormous trees.)

- "Also, it appears European bats may have developed more resistance to White Nose Syndrome" I think that's right. I believe the disease in Europe is somewhat different, and the species are different too (as with other animals, there are species that are very distant relatives that have evolved over time).

- Research has also been done on sonic deterrents, as the post suggests. And so the issue comes down to economics--how many 'noisemakers' do you need to cover the rotor's swept area and where should they be mounted, and how much do they cost, versus using operational changes (the algorithms mentioned previously) instead.

- Yes, climate change will have a massive impact on habitat.

Tom Gray said...

The American Wind Energy Association's (AWEA) info on this is here. I see I was mistaken, in that they've worked on slowing turbine rotation during migration periods, as opposed to changing "cut-in" (start-up) speeds.

Russell Seitz / Bright Water said...

Brian , this is terrible news for French fried bat fanciers, but much as these stats may grieve your Vanuatuan constituants, need something better designed to sustain indignation, like the bat to pheasant or duck turbine mortality ratio.

Fernando Leanme said...

We need to make genetically modified bats and birds able to avoid turbine blades. Another option is to place sirens on top of the wind turbines and have them blast loud noises during bat flying hours. I don't have any more bright ideas.

Fergus Brown said...

Extensive research on bat migration and feeding habits in Europe, linked to Eurobat 2000, a very forceful directive protecting species in Europe, have resulted for many years in mandatory bat surveys being undertaken on almost all wind turbine projects before consent is given by planners, often, even in cases where turbines are very small, domestic, not commercial.

As a consequence, a huge amount of data has been gathered and analysed, especially related to bat risk and wind turbines.

Bottom line is that you can get consent for a turbine in an area with a resident or migratory bat population if you stay at least 50 metres away from known transit routes (mostly hedgerows or field boundaries) and if the sweep of the blades does not descend below the nominal maximum altitude of the species concerned, which is generally below 30m AGL. This is because, with these conditions, the bat mortality rate is negligible, and below the acceptable risk threshold as defined by the directive.

As with almost every other BS excuse for objecting to wind energy, there is already plenty of evidence that demonstrates that sensible turbine placement has no impact on bat populations. As with every other BS environmental objection to wind energy, such claims invariably overlook the many environmental benefits, not least amongst which is that bats won't fry or starve in future as a result of climate change, which is, of course, a far greater existential threat than turbines.

Be clear on this - all environmental objections to wind turbines which do not relate to the specific placement of specific projects in potentially damaging areas (were they won't get permits anyway), are proven to be total BS.

Russell Seitz / Bright Water said...

The world needs a definitive report on the impact of wind turbines on wombats, and Frenando is the man to write it.

Susan Anderson said...

The experts in this comment section, whom I limit to Fergus Brown, who actually knows what he's talking about and Russell Seitz, who puts up with a lot of bull/bat excrement and retains his sense of humor, are worth a good hard look. The rest need to stop letting manipulation pull their chains.

In the day of Trump, emerging from the woodwork is every kind of anti-human pro-moneymaking hot air, ably supported by the kind of links, exhibits, and formulae that plausibly imitate real science, but in fact do no such thing.

Stop letting people pull your chain and move the goalposts. Things are bad enough without doing that.

Susan Anderson said...

Tom Gray is good too. TG, apologies ...

Fergus Brown said...

Russell, you wouldn't believe the difficulties caused by Great Crested Newts. If only this was a joke...

Russell Seitz / Bright Water said...

Newt has seemed rather crestfallen of late, but discovering the Russians selling arms to the Taliban is a reversal of fortune hard for any conservative to bear.

Beakers said...

Just to add to what Fergus wrote, when anti wind liars suddenly profess a deep concern for the plight of birds, I point them to the two years of intensive study of actual birds around actual turbines on the edge of one of the UKs most important migratory bird sites (an SPA and Ramsar site).
https://www.ecotricity.co.uk/our-green-energy/our-green-electricity/from-the-wind/wind-parks-gallery/bristol-port-avon
The activity of these liars has however been successful, in England we have new planning policy introduced in 2015 specifically designed to scare away investment in wind turbines. Planning policy specific to on shore wind power and contrary to the fundamental principle of our Town and Country Planning Act. All to appease liars like Chris Heaton Harris MP, https://en.wikipedia.org/wiki/Chris_Heaton-Harris.

Fernando Leanme said...

I took a course on enviromental activismo by the Sierra Club, and i learned to use several techniques useful to horrorize the public. For example, here's this article

"Wind turbines are actually slaughtering millions of birds and bats annually

The Obama administration is issuing 30-year permits for “taking” (killing) bald and golden eagles. The great birds will be legally slaughtered “unintentionally” by lethal wind turbines installed in their breeding territories, and in “dispersion areas” where their young congregate (e.g. Altamont Pass).

By chance (if you believe in coincidences), a timely government study claims wind farms will kill “only” 1.4 million birds yearly by 2030. This new report is just one of many, financed with taxpayers’ money, aimed at convincing the public that additional mortality caused by wind plants is sustainable. – It is not.

Dr. Shawn Smallwood’s 2004 study, spanning four years, estimated that California’s Altamont Pass wind “farm” killed an average of 116 Golden Eagles annually. This adds up to 2,900 dead “goldies” since it was built 25 years ago. Altamont is the biggest sinkhole for the species, but not the only one, and industry-financed research claiming that California’s GE population is stable is but a white-wash."

Link. http://savetheeaglesinternational.org/new/us-windfarms-kill-10-20-times-more-than-previously-thought.html

I also learned to put this on Twitter. But my Twitter account is mostly used to overthrew Maduro, and this keeps me really busy (feel free to follow me, I put a lot of info in my tweets). Anyhow, this type of argument is very similar to what I see being used to stop harmless fracking operations. It's what goes on in these days when nobody knows if what they know is for real.

Beakers said...

Altamont Pass is a very early windfarm, and lessons learned from that would make building anything similarly harmful now, highly unlikely.
As for the permission to 'Take' in many countries killing a protected species is a criminal offence so even if your activities are highly unlikely to kill the protected species and certainly wont adversely impact the population, you may have to have permission to 'take' so that you dont end up in jail if the unlikely death does occur.
In NZ, it is illegal to kill or harm a seal, so the road contractors rebuilding the earthquake damage to State Highway 1 have this same permission to take. They will not seek to kill, and will actively take measures to protect seals while working, but should a falling rock crushing a seal be attributed to work on the road, no excavator operator or site supervisor will go to jail.
But well done you for your deliberate and dishonest scaremongering.

Fergus Brown said...

Fernando has been cut and pasting from dubious sources again.
If i were being charitable, I'd suggest he was just being provocative to tease us. If otherwise, I would suggest he is being Fernando As Usual.

Bernard J. said...

"I took a course..."

Yes, and I suspect that you're in dire need of a repeat script.

Russell Seitz / Bright Water said...

Fernando, if you think wind turbines are bad for birds, why don't you but a slingshot and lobby for an open season on cats ?

If your numbers are correct , for every bird knocked down by turbine blades today, several thousand are chomped to death by the nation's seventy-odd million kittys

Susan Anderson said...

Fergus, Newt Gingrich, a power behind the throne for decades, who did major advance planning for Trump, and probably brokered the large number of Kochtopus "experts" in office, is no joke. You have to be on this side of the pond to appreciate how awful he is (though Doonesburgy did him with floating bomb-acolytes so ago that I can't find a single image).

Here's a different cartoon that gives you the hypocrite behind the curtain: https://conservaliberals.files.wordpress.com/2012/01/newt-joke.jpg