Not seeing stars?
Connect with your dark side: nature needs the night
This is a picture of light pollution around Didcot and East Hagbourne.
It’s a big deal
Light pollution is a global environmental issue. 55% of the UK population live in areas where light pollution obscures the stars. Darkness at night-time is a key part of rural life, but increasingly, light pollution from direct illumination and “skyglow” disrupts local and even distant ecosystems. It’s a new threat as cheap energy-efficient LEDs light up parts of the world previously dark for the whole of evolutionary time. Animals cannot evolve fast enough to adapt to the changes we are making- they need the night.
Why does light pollution matter?
Well, for a lot of reasons…
Bacteria and algae are critical to life on earth. Bacteria are the structural pillars of our ecosystems; algae produce 30 -50 percent of net global oxygen available to humans and other terrestrial animals. Without light pollution both bacteria and algae have clear winter and summer communities, which can be lost after just one year of artificial light pollution.
Migratory birds are distracted from normal migratory routes by artificial light – resulting in longer journeys, exhaustion and starvation – and reduced bird populations. UK swallow populations are in decline, in parallel with insect decline, and there are well-documented cases of mass mortality of nocturnal migrating birds as they strike tall, lit buildings, with US figures showing losses of 4m birds annually.
Amphibians and mammals are affected by sudden increases in illumination from security lights which reduce visual capability, taking them minutes or even hours to recover, making them vulnerable to predators.
Night flying insects including moths are attracted to light, especially light with an ultraviolet component or a high blue spectral content. Artificial lighting affects insect flight distances and reproduction, threatening genetic diversity and increasing predator threat as insects congregate around lights. A third of flying insects attracted to external lights will die as a result of their encounter.
Owls: several owl species, including long eared owls, are particularly sensitive to artificial light, which disrupts their ability to hunt at night.
Bats: The UK has 18 bat species, all of which have suffered dramatic reductions in numbers in the past century. Light falling on a bat roost exit point delays them from emerging, which shortens the amount of time available for foraging. Britain’s rarest bats are among those species listed as avoiding artificial light, and well-lit areas can become a permanent barrier to them commuting to preferred feeding sites, with devastating consequences.
Pollination: Fewer visits are made by nocturnal pollinators to plants and crops in light-polluted areas, shown in research to lead to a fall in fruit production of 13%.
And last but not least: human health: Exposure to artificial bright light at night suppresses melatonin secretion, disrupting sleeping patterns and impacting physical and mental health.
But you can make a difference!
Consider how you can avoid light spill. Minimise the spread of light.
Avoid lighting up trees that could be roosts or feeding sites for bats, owls and other nocturnal wildlife.
Focus lights downwards – just on the objects you need to see.
Avoid blue rich lights - these pose the highest risk. If you need outside light, use low energy ‘warm’ light bulbs.
Keep your garden dark: remove or switch off outside lights when not needed – and ask your workplace and your neighbours to do the same.
By turning off lights you save money, and help to save nature.
For more information:
https://www.britastro.org/dark-skies/cfds_environment.php?topic=environment