At a meeting of the Louth branch of Lincolnshire Wildlife Trust, we were treated to a talk by John Clarkson, local birder. John spends much of his life sitting near or walking around windfarms. For offshore sites a boat is required. His job is to watch the birds, identify them, count them, track their movements and general behaviour as they interact with the windfarms. Windfarm developers have to commission such studies as part of the planning process.
We learned that birds sometimes die as a result of collisions with wind turbines. There was the celebrated case of the white-throated needle-tailed swift, only three records of which exist for the
British Isles. The last specimen to stray the thousands of
miles from its normal home in eastern Asia died, to the
consternation of the throng of birders that had gathered to watch this rarity,
when it flew into a turbine.
However, it soon became clear from the data that John presented that wind turbine mortalities pale into insignificance beside the bigger dangers of buildings with windows, cats, motor vehicles and pesticides. The clear message is if you want to reduce bird mortality don’t have a cat. Harder to quantify, we heard, but by far the most significant impact on bird populations is habitat loss. More of that anon.
John’s detailed observation reports and the records of radar tracking over the
North Sea were fascinating. Birds, it seems, are well able to see wind
turbines and take avoiding action – flying round them. An exception, in Spain,
is the gryphon-vulture, which flies with its head down looking at the ground
and not watching where it is going!
Spanish windfarm operators have, however, greatly reduced mortality by
keeping a lookout for approaching vultures and stopping the turbines for a few
minutes, with negligible loss of electricity generation, while the vultures
sail safely by. British and Danish bird
observations show that almost all daytime bird flights are low down, below the
height of turbine blades. This is
especially true at sea where almost all birds fly within a very few metres of
the waves. Close observation of a group
of marsh harrier nests within a proposed windfarm site concluded that the birds
hunt close to the ground. Radar tracking
of night time migration flights shows that birds fly very much higher, way
above the turbines.
A survey of a
windfarm and adjoining farmland showed a greater population of small birds
marking their territories with song within the boundaries of the windfarm. The varied habitat of access tracks and rough
ground provided an improved habitat compared with the neighbouring arable
monoculture. The biodiversity associated
with windfarms should be considered a bonus.
For off-shore windfarms this effect may be even more significant since
turbines prevent the large-scale trawling operations that have destroyed so
much of the North Sea’s bed habitat and the turbine
bases provide structures for reef formation and an explosion of biodiversity.
In the question and answer session that concluded John Clarkson’s talk, it soon became evident that several of the wildlife-loving audience were against windfarms. Some folk just do not like the look of turbines in the landscape, and it’s hard to argue against personal aesthetics. They rarely say so explicitly, preferring to come up with other excuses that attempt to be factual rather than subjective. Most such arguments fail miserably. One lady talked of the vast amount of concrete (there’s really only a little concrete used per unit of electricity generated) and that in 25 years when the turbine would be removed the concrete would be left in the ground. I’ve no idea where the idea that after 25 years the turbine will be removed came from, as if in the year 2039 we will no longer want electricity. It seems more likely that as and when turbine components wear out they will be mended or replaced, with its concrete base having a pretty lengthy serviceable lifetime.
Now recall that John had suggested that far and away the biggest threat to our bird population was habitat loss. It was upon this theme that I drew attention to the long term habitat loss that is inevitable in a business as usual, fossil-fuel burning future, in which global warming will push average temperatures 4 or more degrees higher within the lifetimes of our younger children and grandchildren. We had a choice, I pointed out, of either producing our electricity from renewable sources or doing without power. The alternative, our present course of carbon emissions, inevitably leads to habitat loss on such a world-wide scale that discussion of whether birds crash into turbines is utterly irrelevant.
There were, sadly, immediate mutterings of disbelief and opposition from some in this audience of nature lovers. Denial of science is evidently rife within what one might assume was a fairly intelligent and informed group of people. Such is the depth of feeling, the subjective loathing of windfarms, that rational discourse is set aside. Somehow we have to convince these doubters, not only that the science is right, but that the future is bleak beyond imagination; that a 4 degree world is just not going to be survivable for vast swathes of the global population, either of humans or of birds.
Of course many people realise the truth and I am personally grateful to the lady behind me who thanked me for being brave enough to voice what she had been thinking. And that brings me to the conclusion that it’s time to stop being polite about global warming, ducking the contentious issues, avoiding confrontation with deniers, whether they be fools or knaves. We need to shout out that policy and behaviour change must come, quickly, urgently; we need radical emissions reduction policies, now. We, the people, need to empower the politicians and legislators to change direction. When someone mutters nonsense about doubting the climate science we must look upon them in the same way as we would one who claims the Moon is made of cheese. After all, anyone can see that the Moon is the colour of a Wensleydale so of course it must be dairy produce.