Today marks the final day of Dark Sky Week, which is hailed as a global celebration of the night and a call for less light pollution.

In some cities internationally, local governments are trying to find a solution to lighting the night that can better serve critical wildlife ecosystems and humans alike.

Malcolm Brabant reports from Denmark.

It's dusk in Gladzaxa, a municipality north of Copenhagen that prides itself on combining urban growth with environmental initiatives.

Gladzaxa was the first Danish local authority to install red street lighting that helps reset the balance between

human beings and the animal kingdom. The council removed conventional white spectrum street

lamps from this stretch of road next to a large bat colony in the trees. Artificial white

light is hugely disruptive for a broad range of creatures.

For example, bees get a form of jet lag, frogs lose their libido, and bats find it difficult

to catch food.

Red light enables bats to see in the dark, unlike white light, which blinds them.

This simple solution to restoring bats night vision has been adopted in

Metz in Eastern France, Worcestershire in the British Midlands, Germany, the Netherlands, Belgium,

and its spreading. Every light source we put up changes some balances, move things around,

makes it easier for some animals to find a mate, get food, and makes it harder for someone else.

Runa Brand Hermanson was one of the designers behind the Red Light project in Gladzacca.

We need to take care and try to change and affect our surroundings as little as possible.

And a lot of lighting is actually there for no one's sake.

I'm not an advocate that we should not have lighting for humans.

I'm an advocate that we should try and have as little lighting as we can

so we can offer more darkness for nature.

Biologists say that people need to recognize the importance of bats in the ecosystem.

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