I’d heard of nature reserves, marine reserves, and national strategic oil reserves. Dark reserves are a new one to me, but Britain got its second this month. Brecon Beacons National Park, in Wales, has just been declared an international dark sky reserve. It joins Exmoor National Park as the two places in Britain so far where the dark has special protection.
I suspect I’m not the only one that finds it rather surreal that there are conservation agencies dedicated to saving the dark. In this case, it’s the International Dark Sky Association that’s made the award, but there are others.
The issue, of course, is light pollution – excess light. There are lots of sources of it, from streetlights to billboards, parking lots and illuminated buildings and monuments. It manifests itself as a dull glow on the horizon that obscures the natural dark sky, and the stars. It’s a problem that has got worse in many parts of the world over the last few decades. We like lighter cities and we feel safer in them. Aside from the aesthetics of the night sky, is it really a problem?
Excess light does have consequences for wildlife. It’s hard on bats, who can get confused about when it’s time to get up and feed. Birds can get confused over when dawn might be and can miss key feeding times, say the RSPB . Light pollution may one of the many reasons for the decline of small birds such as sparrows in Britain’s towns and cities.
A bigger issue is the waste involved. In an age where energy is expensive and budgets are constrained, are we sure we need to be illuminating the sky? It’s a waste of electricity and a drain on the public purse. Britain has 7.5 million street lights. More modern ones direct the light better, but many spill as much as 30% of their light upwards. The Campaign for Dark Skies estimates that this accounts for 830,000 tonnes of CO2 annually, just from the wasted light. Switching some of them off would save council budgets and reduce CO2 emissions.
But how comfortable are we with the dark? Not very, if previous light-saving initiatives are anything to go by, with crime the biggest reason for opposing them. This is unfortunate, since the link between lighting and crime is actually rather more complex than one might assume. Sometimes more light reduces crime, other times it simply displaces it, and in some cases it can even increase crime. Generally speaking, switching off the lights doesn’t make us less safe, but it does make us more scared. That’s the conclusion of government research, which found that “lighting improvements are in general more likely to have a positive effect on the public’s fear of crime than on the incidence of crime itself.”
It’s just as well that switching off the lights doesn’t normally raise crime levels, because it is becoming quite common. A survey last year found that almost three quarters of councils in England had either dimmed or switched off some streetlights, or were planning to do so. Most of us won’t ever reach the specially protected levels of darkness of the Brecon Beacons, but perhaps austerity will do more for the night sky than any of the campaigns have done so far.