Ecology
A moth driven to light. Every child knows this proverb. Birds, as well, follow the inviting light beam, too often to their deadly end. Light interferes with orientation in many animals, it can attract or repel. It also influences the hormons in many species and thus interferes with reproduction and development. Entire ecosystems becomes unbalanced, because some species avoid light while others, e.g. spiders, use the light to catch their prey.
„What if we woke up one morning and realize that we missed half of the story in our conservation efforts, namely the night part?”
Catherine Rich & Travis Longcore, Ecological Consequences of Artificial Night Lighting
Humans, being a diurnal species, tend to focus on the activities and needs of other diurnal organisms. In this we fail to understand the night as a habitat in itself, with nocturnal species showing a variety of night-specific adaptations. Today, city nights can be a thousand times brighter than natural nights with a full moon. This might have dramatic consequences for the behaviour of nocturnal animals. Diurnal animals, similar to humans, might suffer from sleep disorders if they can't sleep in adequate darkness.
If we keep replacing the night by an artificial day, we face incaluable ecological consequences. Sustainable lighting must not solely be defined by energy efficiency, but equally by its effects on the local fauna and flora. This includes considerations of direction of light, lighting times, light intensity, and wave length (light colour and temperature). Intelligent, intredisciplinary light planning is a way to reduce the damage of lightpollution.
Blogposts about this topic
Light pollution and birds - Part 1: Journey to Death
Green gardening around the clock
Nature- and neighbour-friendly Christmas lights
The LakeLab at Lake Stechlin: Studying the impact of artificial light at night on aquatic ecosystems
Is a 4000 Kelvin LED street light like the moon?
Bats in the spotlight: winners or loosers?
German blogposts about this topic
Meeresschildkröten auf Abwegen
Die Nacht schützen: Forschernetzwerk veröffentlicht Empfehlungen für Aussenbeleuchtung
Photo: Insects at a luminaire, by Nevit Dilmen (Diskussion) (Own work) [CC BY-SA 3.0], via Wikimedia Commons