A Q&A with Johan Eklöf

Emily Porter

February 15, 2023


Scientist Johan Eklöf guides us through the darkness in his new book The Darkness Manifesto. Through this book you will explore how the night affects our body's functions, the ecosystems around us, and how we can be better allies of the night.


Most humans take the night sky for granted. We artificially illuminate our homes, inside and out, perhaps without realizing the repercussions. What is the unnatural light doing to the animals and plants that need the precious few hours of darkness to reproduce, grow, and survive? How does unnatural light at night affect our circadian rhythm and overall wellbeing? If you have ever seen the true night sky without the glare and fog of light pollution, you have felt that awe and know that other generations should experience this wonder as well. Scientist Johan Eklöf guides us through the darkness in his new book The Darkness Manifesto. Through this book you will explore how the night affects our own body's, the ecosystems around us, and how we can be better allies of the night.  



Porchlight Book Company: What began your investment in protecting and researching bats, these beings of the night? How have they made you think differently about the night?

Johan Eklöf: Researching bats, I applied for a PhD-position with Jens Rydell (professor at Gothenburg university at the time). I liked him as a teacher and I chose him, not the subject. The bats just came along. But I was soon hooked. Bats are amazing. And working with bats means working at night, which made me discover that darkness is relaxing, that there are so many things coming to life after sunset: different smells, sounds, subtle movements. I realized that the night is underexplored and extremely underestimated 😊    

On expanding his research from bats to other night creatures: 

If beings mean any night creature: I was investigating how flood lights on churches affect bat colonies living in the church attics and towers, and found that in 30 years, half of the colonies of brown long eared bats had moved away (or worse). It struck me how little thought I’d given this problem. There must be so many animals affected by this. I started to read whatever I could find, to write a defense of the dark.


Porchlight Book Company: You talk about how insects are dying from light pollution on a grand scale, and if it continues at the rate of a 3% decrease annually, most of them will be gone in one hundred years, which would be detrimental to us all. There are so many reasons that humans don’t like insects: they aren’t cute (I think some are!), they aren’t welcome in our homes, and they’re pests when we’re outside too. Why should we care more about insects?

Johan Eklöf: Yes, it’s much easier wanting to save pandas and tigers. In theory, we understand insects are important, but we do not really miss them if they go away, perhaps apart from butterflies and bumblebees. However, in recent years many people have been involved in saving bees, planting flowers for insects and many other things. But we have forgotten about the night insects which are equally important for pollination.

Porchlight Book Company: Do you think that we will, as a society and species, learn how to coexist with nocturnal animals, therefore protecting ourselves and other beings in the long run?

Johan Eklöf: Hopefully, one day. I see changes in attitude already, but I think we are far from accepting a darker night. The use of artificial lights will continue to increase. But I also think that motion sensors and timers will be used more and that we will stop using white light at night. Perhaps there will be more shielded lights and lights designed for both humans and nature. 

Porchlight Book Company: You state that few people know what the true night sky looks like. I have seen this for myself when hiking and living near Zion National Park in Utah, and I must say that the memory will always be with me. It almost looked like diamond dust was blown across the sky, pure magic. In your book, you speak about how there are designated areas that are protected from light pollution. How strict are darkness laws, and are they enough to protect that given area on their own? Or will there need to be more environmentally protective laws in place to prohibit other forms of pollution, too?

Johan Eklöf: Most dark parks are supported by local authorities and run by enthusiasts. Some countries have laws against light pollution, limiting intensity and the time lights can be used, but they are few. We need stricter regulations about lighting, and we need to acknowledge light pollution as a true problem. In conservation, biologists often work with the concept of green corridors. We should add darkness as a component of the “green”. 


Porchlight Book Company: In the book, you mention that both nocturnal ecosystems and human bodies are negatively affected by artificial light. Do you think it is possible to get back to our natural baseline or do you think that our sleep and metabolism will continue to get worse based on our modern-day lifestyles and technology?

Johan Eklöf: I think it’s hard to go back and we have probably not seen the worst yet. But we can mitigate the problem by using less intense, fewer, and not as white light. If we start using lights only when we must, it’ll get easier to find darkness.


Porchlight Book Company: I never realized that birds were drawn to the light of the moon, or unnatural light, like that of an insect. It makes complete sense, but I think most of us do not think about this aspect of how light pollution can harm insects and birds trying to migrate. During the yearly bird migrations, it is important to dim or extinguish your lights past dusk so they do not collide with your windows on their way to southern temperatures. Can dimming or turning off just your house lights past dark or other simple tasks have a huge impact on these creatures?

Johan Eklöf: I also was a bit surprised at the magnitude of the problem, from birds to marine plankton. How this will affect birds in the long run is hard to tell, but many species are decreasing. I think every little step is important. If we all dim our garden lights, complain about flood lights shining in the middle of the night and shield off light so that no light escape upwards, birds will stand a much better chance finding their way at night.


Porchlight Book Company: I can relate to feeling comforted and being able to open up when having conversations with my partner right before bed, when the room is dark, as you discuss in the Extinguished Conversations section. We value light so much, but how can we value the darkness that our natural self seeks? Do you try to practice allowing darkness into your own everyday outside of your work and research?

Johan Eklöf: A little bit. I end the day by taking the dog out in the garden, looking at the sky for a while. Sometimes I turn the light off at home, just resting in the dark or listening to a book or a podcast without the lights on.


Porchlight Book Company: In the book you explain how different cultures throughout history thought about light and darkness. Some saw light as being good and darkness as evil, others saw darkness as just the opposite of light and nothing more, but both are necessary and needed in the overall balance of things. As many countries are making strides in bringing darkness back—through darkness parks, lights out after a certain time or even altering the light source ito lessen negative effects—do you think many other countries will jump on, or will it be harder to get certain countries on board?

Johan Eklöf: I don’t know. I think it is just as with many other environmental issues:, it depends more on the government than the culture. At the same time, it is hard to deny developing countries the opportunity of having just as many electric lights as in US and EU, for example. We must show the way and then share as many fauna-friendly lighting solutions as possible.


Porchlight Book Company: Most humans have a rational, instilled fear of the dark, yet it can help us destress and calm our bodies and minds. People may even be surprised by how inviting the natural light, can help our bodies, minds, and outdoor ecosystems. Do you see a future where some, if not most, of us go back to candles and living by the sun as we did in the past?

Johan Eklöf: Yes, and we still do at times. We choose a candlelight dinner over a bright fast food place if we can. People still enjoy a fire by a lake. But our fast, 24/7 society makes it hard for us to just sit down and enjoy those things on a regular basis. We need to change our priorities.


Porchlight Book Company: Do you think we have time to act, to change this around and save the night, save ourselves? I know a very loaded question! The book is full of hopeful prospects but also a dire plea to act fast.

Johan Eklöf: It is possible, as I have said in some previous answers there are some laws already, dark parks and a change in attitude. But perhaps it is just too slow, as with climate change. We need to work faster. We have a huge ship to turn around. Probably we will never go back as it was just 30 years ago, but hopefully we will learn to save and appreciate darkness at least to some extent.


Porchlight Book Company: Can we look forward to any future projects you have in the works? 

Johan Eklöf: Yes, but it is a bit too soon to give away. But I will stay in the world of twilight. 


About The Darkness Manifesto: On Light Pollution, Night Ecology, and the Ancient Rhythms that Sustain Life

In the bestselling tradition of Why We Sleep and The Sixth Extinction, an urgent and insightful look at the hidden impact of light pollution, and a passionate appeal to cherish natural darkness for the sake of the environment, our own well-being, and all life on earth.

How much light is too much light? Satellite pictures show our planet as a brightly glowing orb, and in our era of constant illumination, light pollution has become a major issue. The world’s flora and fauna have evolved to operate in the natural cycle of day and night. But in the last 150 years, we have extended our day—and in doing so have forced out the inhabitants of the night and disrupted the circadian rhythms necessary to sustain all living things, including ourselves.

In this persuasive, well-researched book, Swedish conservationist Johan Eklöf urges us to appreciate natural darkness, its creatures, and its unique benefits. Eklöf ponders the beauties of the night sky, traces the errant paths of light-drunk moths and the swift dives of keen-eyed owls, and shows us the bioluminescent creatures of the deepest oceans. As a devoted friend of the night, he writes passionately about the startling damage we inflict on ourselves and our fellow creatures simply by keeping the lights on.

The Darkness Manifesto depicts the domino effect of diminishing darkness: insects, dumbfounded by streetlamps, failing to reproduce; birds blinded and bewildered by artificial lights; and bats starving as they wait in vain for food insects that only come out in the dark of night. For humans, light-induced sleep disturbances impact our hormones and weight, and can contribute to mental health problems like chronic stress and depression. The streetlamps, floodlights, and neon signs of cities are altering entire ecosystems, and scientists are only just beginning to understand the long-term effects. The light bulb—long the symbol of progress and development—needs to be turned off.

Educational, eye-opening, and ultimately encouraging, The Darkness Manifesto outlines simple steps that we can take to benefit ourselves and the planet. In order to ensure a bright future, we must embrace the darkness.

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