- Would you be willing to live in a blood-red town to help animals?
The streetlights turn red, bathing the dark street in an eerie crimson glow. From the blackness of the night, bats soon begin to dart back and forth between the shadows.
You might think Dracula himself is about to appear and sink his teeth into your neck. But don’t worry, there are no vampires around.
You’re just in Denmark.
The Danish town of Gladsaxe has decided to replace its white streetlights with red ones. The unusual move is intended to provide a more hospitable environment to local bats.
The bright daylight or orange bulbs of conventional streetlights can deter bats while attracting insects, simultaneously shrinking the bats’ territory and depriving them of food. However, the red light doesn’t bother bats, so the town hopes the new lights will help them thrive.
At the same time, the red LED bulbs consume less energy than the old lights. Although the red lights will initially be installed as an experiment along a short stretch of road, they may become more widely used if the test is a success.
Saving money while protecting bats – what’s not to like? Well, apart from making the streets look like a horror movie set.
Bats at Risk
Gladsaxe is a Danish municipality, located just outside the capital city of Copenhagen. Some time ago, the town government decided to start replacing its old streetlights.
While doing so, they determined to help local bats. Environmental researchers had discovered that the nighttime flyers weren’t dealing too well with the town’s streetlights.
According to Gladsaxe authorities, the town is home to seven bat species. Although none of them are endangered, two of the bats – the pygmy bat and the long-haired bat – are at risk of roads getting in the way of their normal activities.
“We wanted lighting that would affect the bats and nature as little as possible, without compromising traffic safety,” said Jonas Jorgensen, a road engineer working for Gladsaxe Municipality.
So, the town has chosen to install unusual red streetlights.
Why Red Lights?
Red streetlights are indeed odd, but there’s a reason why Gladsaxe went with them. All light is not equal, and some kinds of light are more disruptive to animals than others.
In case you slept through your physics classes, light’s wavelength determines its color. White and blue light, which our regular lightbulbs and screens spew out, have short wavelengths. Red light, on the other hand, has longer waves.
Bats, as you surely know, are nocturnal animals and shun short-wave daylight. As such, when they see white streetlights, they steer clear of them. Inadvertently, this restricts the area in which bats can hunt.
While bats hate white light, bugs infamously love it. As the streetlights draw insects toward them, bats are reluctant to follow, which in turn reduces the amount of food available to them.
Red light, however, doesn’t seem to bother bats. Perhaps its unnatural color doesn’t trigger their “Ew, daylight!” response, or maybe they can’t see it in the first place.
Whichever the case, bats can freely fly through red light. At the same time, insects don’t care about it either, so nothing stops the bats from chowing down.
But what about us human road users? Well, our eyes can see just fine in red light, so the new bulbs won’t affect road security from our perspective.
They do make the streets look like they’re bathed in blood, but hey – you can see them.
Energy Savings
Outside animal welfare concerns, there’s another good reason for Gladsaxe to change its streetlights. The new red LED lights will consume significantly less energy than the town’s previous ones.
Four-fifths of Gladsaxe’s streetlights still use old-fashioned lightbulbs, which tend to guzzle power over time. Swapping to LEDs (whether red or any other color) will save at least 7.2 million kilowatt-hours of energy, the town notes.
That will, of course, mean lower power bills for the town. The saved funds can then be used on other projects.
Small Initial Experiment
However, nobody knows yet if the red lights will ultimately prove too distracting to locals. As such, Gladsaxe isn’t immediately swapping every streetlight for red LEDs.
Initially, the town is converting about 5,000 light fixtures along a single road. This road is the local bat hotspot, so it makes sense to start there.
If the initiative is successful, the town intends to install new LED streetlights in other areas. However, not all of them will be blood-red, as the red bulbs simply aren’t necessary in places where the bats don’t live.
And that’s probably good for Gladsaxe residents as well. Even if it wouldn’t bother their vision, turning the entire town crimson at night might be a bit too creepy for people’s mental well-being.
Not quite sure if you’re okay with bats? Check out our 10 strange facts to help you appreciate bats!