Holiday lights illuminate most communities’ streets, homes, and public spaces because nights are lengthening in the dead of winter. While human life and spirits are bright, lights pose enormous challenges to the smallest of creatures sharing the planet with humans: nocturnal insects and animals. Researchers are shedding light on artificial lighting’s ecological impacts–especially on insects, to find ways to be more wildlife-friendly with decorations of the seasons.
“It has been well established, even in the scientific world, that artificial light at night really affects arthropod activity,” said Daphne Chevalier. “I am looking more closely into that, focusing on more ground-dwelling species; basically, anything that gets found scurrying around along the ground.”. Her work is part of a growing body of evidence that nighttime lighting is bad for ecosystems. “Insects are integral to ecosystems,” says Chevalier. “They are pollinators, nutrient recyclers, and food for other wildlife.” Artificial light can disrupt these important functions with important long-term ecological implications.
Nocturnal pollinators, such as moths, can be attracted to artificial lights and die. Rather than flowers, these insects are lured in by the light and energy is wasted flying round luminescent objects that becomes easy prey or exhaust for them. Night lights, studies have proven significantly diminished the rate of pollination. One such research presented it decreased by 62% when lights are active. Ground dwelling like beetle and wood louse activities too are disrupted, wherein the soil and all associated ecological processes maintained by the nutrients being recycled by these creatures get upset.
Even though the insects are depressed during winter, their presence is crucial. Birds that overwinter require insects as a food source, and therefore, it highlights the interconnectivity of ecosystems. Beyond the insects, artificial lights affect a huge number of nocturnal animals. Birds are most vulnerable, and millions die annually from collisions with brightly lit buildings. Such buildings invite immense populations of birds that lose their orientation and increase the chance of fatal collisions. Moreover, species like bats and owls depend on darkness to hunt and seek refuge, whereas excessive lighting enters their natural habitats.
Such damage will not befall humans at the negative impacts of artificial lighting. Outdoor displays with lightings such as cool toning that interfere with sleep via the impact on circadian rhythms would lead to probable health problems on a chronic nature. So, the argument for consideration of light’s use during night is important not only from the aspect wherein human beings recognize its value toward festive celebrations.
This is from Chevalier’s ongoing work in the UBC plant-insect ecology and evolution lab, where she focuses on the ecological consequences of artificial night light. Most of these studies have been done in non-urbanized areas and involve ground-dwelling arthropods, but her results simply add to an overwhelming trend that describes how human activity impacts otherwise natural systems. These sorts of results may be especially relevant during holiday lighting.
For those who do want to celebrate responsibly, Chevalier offers a few simple tweaks to holiday lighting that can mitigate harm to wildlife without sacrificing festivity. A first step is to use a timer to control when lights are on. Many animals are most active at dawn and dusk, so scheduling lights to turn on after dark and switch off by bedtime cuts down on disruptions.
Light placement matters, too. Lights that shine above eye level, and especially lights shining up, contribute to “skyglow,” in which light scatters to form a halo that can attract animals from miles around. The effect can be limited by installing lights under overhangs of roofs or through windows. Trees and shrubs offer sheltered nesting sites for chickadees and squirrels and the like. Leaving these areas dark, or decorating them with non-illuminated ornaments, protects their habitats while still providing a festive look.
This sums up to the wildlife-friendly practices. Warm-tinted, low, and steady LEDs are preferred over cool-tinted or flashing lights that may confuse or attract animals. In addition to saving more energy, these options create a cozy, inviting glimmer that is less disturbing for both wildlife and humans.
Ultimately, these thoughtful adjustments reflect a broader commitment to coexistence with the natural world. As Chevalier emphasizes, “By decorating with care, you’ll be fostering coexistence with wildlife and supporting biodiversity in your community—without having to compromise on holiday spirit.”
The holiday season is a time for all of us to reflect on the need to balance the joys of human life with good stewardship of the earth. Mindful lighting is one way communities can celebrate their festive seasons without letting merriment blind them to hurting the smallest neighbors who roam, fly, or hunt under the veil of darkness.