This book was incredibly eye opening in regards to the impact of light pollution on all non-humans and humans alike. As an outdoor lover who grew up in a place without a ton of light pollution, I was unaware of the impact until reading this book!

This was an enlightening, short read on the ecology of various nightlife and the impacts of light pollution on the Earth's ecosystem. In our modern lives we rarely take time to consider how conveniences we take for granted impact the world around us.

Super interesting. Living in a city I’ve noticed light pollution but I truly didn’t know much about it. Will make me more mindful moving forward of what artificial light dies to us abc other living creatures.

The Darkness Manifesto: On Artificial Light and the Threat to Our Ancient Rhythm, by Johan Eklöf (translated by Elizabeth DeNoma) is a solidly informative book that raises some serious questions and challenges us to think differently about how we might live our lives, though it suffers somewhat from its structure.

Eklöf is an ecologist who specializes in bats, so one can see where he might get his fondness for the darkness of night. The thrust of his book, supported by a myriad of examples from the natural world and our own human experiences, is that the constant illumination of our lives is disrupting the circadian rhythm of all creatures, including ourselves, and that these disruptions are not only harmful to the beings themselves but have cascading effects that harm entire ecological systems and our own ability to sustain our existence, let alone that of those creatures so unlucky as to share this planet with us.

Insects, for instance, are facing a stunning drop in populations and while much of that can be attributed to climate change, habitat destruction, monocultural agriculture, and pesticide use (more on this btw can be found in the excellent if depressing The Insect Crisis by Oliver Milman), we’ve all seen how insects react to light, making it clear that our full-time illumination is also a contributing factor, not only making them easier prey for predators (like Eklöf’s bats) who hang out around street lights for the night’s buffet, but also making it more difficult for them to navigate and to reproduce. As moths are major pollinators (yes, moths), this is a problem that ripples beyond the moth population.

Birds as well are facing their own population decline, and like insects, they too are being harmed by how we light up the nighttime sky, causing them to crash into window, fly in circles amidst the light until they literally drop out of the sky from exhaustion, and making it more difficult if not impossible for them to navigate their way along their migratory paths.

Meanwhile, the host of problems constant light bombardment causes humans is well documented and include, but are not limited to, sleep deprivation, anxiety, depression, and obesity. And while the shift to LED bulbs has been of great benefit to our energy efficiency, as Eklöf points out, that savings has often been plowed back into more lighting, so the energy savings are pretty much a wash while we blast the sky with ever more lights.

While Eklöf specializes in bats, one can see from the above examples he ranges widely across the animal kingdom, covering lights effects on insects, birds, baby turtles, coral reefs and more. He also crosses disciplines to explore human eyesight, explaining how our nighttime vision compares to other animals and why even the smallest moment of light can so fully disrupt that vision once our eyes, as they’re meant to adapt to lower light levels. He also dips into evolutionary biology, fitting the development of eyes into the “arms race” of the Cambrian Explosion and showing how modern-day creatures are changing their behavior to adapt to the newly lit world they now move in.

Eklöf’s prose (with a nod to the translator of course) is always clear and smooth, with an occasional dip into the lyrical, though less often than one might perhaps expect given the topic. And rather than acting as a detached observer or an aloof conveyor of facts, his use of personal experience combined with his clear passion on the topic makes him a personable tour guide to the night,

The one issue I had with the book is its structure. Rather than being a seamless non-fiction narrative, Eklöf presents us with a series of quite brief mini-essays. On the one hand, if you’re the sort who likes to dip in and out of a non-fiction work, taking a week or more to read it, than this might be to your liking. If, like me, you prefer to become immersed in the information and the speaker’s voice, the structure may strike you as more than a little choppy (it did me). And more than once I felt like the essays either ended abruptly or introduced a subject or raised some questions without fully delving into them, leaving me feeling better informed but also a bit disappointed. I would have preferred either a different structure or longer essays, but that’s really my only complaint here (a relatively minor one), making The Darkness Manifesto an easy recommendation.

If you’ve ever noticed that there are less fireflies than before, or that there are fewer insects on your windshield than previous years - this book helps explain why and what the impact of that loss in biodiversity means. From learning why there are less fireflies than ever to understanding that city lights cause turtles to turn away from the sea, this book discusses the impact artificial light has on wildlife. Part memoir of the author’s own experiences in the night sky and definite manifesto for a push against artificial light, this book is a quick read that both fascinates and delights the reader while also exploring the consequences of our human push for more light and what we can do about it to protect our ecosystem and home.

Dark Spring. I read this book and write this review as someone who longs to see that which I've never seen in nearly 40 years of existence on this Earth - the Milky Way as the Ancients did. Here, Eklof makes a case as to why the light pollution that is so prevalent in so many areas of the world needs to be treated just as seriously as any other form of human-made pollution. Indeed, at least in his claims, this is as strong a book against light pollution as Rachel Carson's Silent Spring was all those years ago.

HOWEVER, where Eklof fails a fair degree - and the reason for the star deduction here - is that while he makes a lot of strong claims, there is scant documentation of these claims - coming in at just 15% or so of the text here, when more fully documented books come in closer to 20% - 30%, and books that are particularly well documented can reach 50% or so of the overall text.

Still, as a sort of primer to these issues for those who may not be aware of them already, this is a strong book that will allow for further research after reading it. Very much recommended.