Copenhagen, urban illumination along one major roadway is red, not white.<\/p>\n
The change in colour is part of a scheme to reduce the effects of light pollution, particularly on nocturnal animals.<\/p>\n
Research has shown that bat activity is hindered by white light at night, while red light appears to have minimal effect, akin to darkness.<\/p>\n
European cities install bat-friendly red lighting<\/p>\n
In Gladsaxe, a project by AFRY Architects is underway to help reconcile urban development with environmental goals.<\/p>\n
Red LED streetlights have been installed along a main road and cycle superhighway in order to minimise the impact on the living conditions of bats<\/a> in a nearby colony.<\/p>\n Thirty one-metre-high bollards along the road now emit a red glow.<\/p>\n The bollards are spaced far enough apart to let light-shy species cross the area without being exposed as potential prey, while still allowing vehicles and cyclists to navigate the road safely.<\/p>\n Similar projects have launched around Europe. In 2018, the Dutch town of Zuidhoek-Nieuwkoop became the first in the world to install fauna-friendly red lighting.<\/p>\n The UK created its first bat crossing in 2019 with 60 metres of red lighting along the major A4440 motorway near Worcester\u2019s Warndon Woodlands nature reserve.<\/p>\n Red lighting has no negative effect on bat activity<\/p>\n In 2017, researchers succeeded in measuring the effects of light on different bat species for the first time.<\/p>\n The team from the Netherlands Institute of Ecology found that different spectra had varying effects on the activity of slow-flying, light-shy bats in their foraging<\/a> habitat.<\/p>\n The experiment was conducted over five years at eight study sites along forest edges in dark areas of the Netherlands.<\/p>\n “We’ve found these bats to be equally active in red light and in darkness,” said lead researcher Kamiel Spoelstra in a press release at the time. “White and green light, on the other hand, substantially reduce the bats’ level of activity.”<\/p>\n Related<\/p>\n Bats<\/a> hunt for insects at night because there’s not much competition from other animals, and predators won’t see them because it’s too dark.<\/p>\n White artificial light can cause significant disruption for species such as Natterer’s bat or the brown long-eared bat, which may feel vulnerable to visual predators such as owls.<\/p>\n Agile flyers such as the pipistrelle, on the other hand, don’t mind the extra light, according to the study. In fact, streetlights even help them catch more insects<\/a> by luring them into a concentrated area.<\/p>\n Larger bat species, such as the serotine bat and the lesser noctule, fly high enough to be unaffected by streetlighting, the researchers found.<\/p>\n Red lighting is a practical solution to environmental protection<\/p>\n The research proved particularly positive because red lighting experiments hold up under real-life conditions. “It’s entirely suitable for use on country roads,” said Spoelstra.<\/p>\n