You’ve probably heard about the grave consequences of climate change and pesticide use on insect populations across the world. Still, there is another inconspicuous insect killer in our plain sight – artificial lighting. In the latest bid to reverse the dramatic insect decline, Germany is planning on dimming its lights.
A focus on lighting is a part of the new set of efforts in a strategic proposal by the German environment ministry coined this May. The propositions include partially outlawing outdoor spotlights, reducing herbicide use, and increasing natural habitat protection.
When it comes to lighting, the proposal suggested the following:
- Banning outdoor light traps.
- Limiting the use of searchlights and sky spotlights – ban from dusk till dawn for 10 months per year.
- Installation of new public lights in tune with guidelines for curbing light pollution, and in such a way it minimizes impact on plants, insects, and other animals.
The ‘insect apocalypse’ alarm first went on in Germany in 2017, when a study showed that the number of flying insects plummeted by 75% in 27 years (from 1989). The grim statistics look even worse considering that the samples for the research came from protected natural areas.
In the subsequent analysis by various scientists and teams, artificial lighting emerged as one of the key factors of insect decline, along with pesticide use, habitat loss, and global warming. Considering the fact that about half of all insect species are nocturnal, it is no wonder the impact is so high.
How Lights Are Affecting Wildlife
The presence of ‘unwanted or excessive artificial light’ is called light pollution. Similar to noise pollution, it is a form of energetic waste. While light pollution is probably the most infamous for its visual pollution of night skies and adverse effects on astronomical research, what is less known – but increasingly studied – is the effect on wildlife and biodiversity.
The impact on wildlife also has to do with the interactions of artificial lights and skies. Ever since the invention of candles and possibly as far as the fire’s invention, people have been aware of the ‘moth-to-a-flame’ effect – when moths and other nocturnal insects are extremely attracted towards anthropogenic light sources.
The phenomenon occurs because nocturnal animals use nighttime natural light sources – the moon and the stars – as a means of orientation when migrating or looking for a mate.
The invention and abundant use of artificial lighting has interfered with this process by attracting or misleading nocturnal insects and other animals – sometimes even killing them. The latter is especially true for light traps that attract insects and then deliberately kill them with electric power, although animals can be fatally hurt by other sources of light, incidentally. It is estimated that one-third of insects stuck in the light-bulb ‘orbit’ die by the morning.
Besides moths, other well-known lighting insect victims include fireflies and dung beetles.
However, the influence of light pollution goes beyond insects. Migratory birds that fly by night also use celestial bodies for navigation. Consequently, they are disoriented by the artificial light of urbanized areas and even collide with highly illuminated buildings and towers. The American Bird Conservatory estimates that more than 4 million migratory birds die in the US as a result of these collisions.
How To Curb Light Pollution
As measures proposed by the German environmental ministry suggest, the first step in curbing light is limiting the use of most damaging and unnecessary outdoor lighting. The design of streetlights is also of significant importance, and many improvements have been made in the field during the last decade. Leaving natural areas with no or minimal discrete illumination should also be considered wherever possible.
On the other hand, public LED displays used in advertising and decoration is on the rise and might be a light pollution topic worth tackling in the future.
Individual action can also have a positive impact on minimizing local light pollution. Rationalizing lighting use, covering the windows at night, installing timers and motion sensors instead of keeping the lights on through the night (especially outdoors) are simple modifications every homeowner can put into practice. Nocturnal creatures – and amateur astronomer neighbors – will be eternally grateful.
Germany plans to dim lights at night to save insects. (n.d.). MSN/AFP. https://www.msn.com/en-us/news/technology/germany-plans-to-dim-lights-at-night-to-save-insects/ar-BB17BlkR
Carrington, D. (2020, April 23). Insect numbers down 25% since 1990, global study finds. the Guardian. https://www.theguardian.com/environment/2020/apr/23/insect-numbers-down-25-since-1990-global-study-finds
LED streetlight design reduces light pollution, saves energy. (2013, April 26). SciTechDaily. https://scitechdaily.com/led-streetlight-design-reduces-light-pollution-saves-energy/
Carrington, D. (2019, November 22). Light pollution is key ‘bringer of insect Apocalypse’. the Guardian. https://www.theguardian.com/environment/2019/nov/22/light-pollution-insect-apocalypse
Light pollution. (n.d.). Encyclopedia Britannica. https://www.britannica.com/science/light-pollution