Why dark skies matter more than we think

The North Pennines is widely recognised for its stunning landscapes, rich wildlife and some of the darkest skies in England. The dark night sky is often celebrated for its beauty but it is far more than just a visual experience, it is a vital part of how this landscape functions.

Even though such places can feel remote and untouched, the impacts of artificial light are spreading. Advances in technology, such as remote sensing, have shown that light pollution doesn’t just stay in towns and cities; it reaches much further than we might expect. Even small, isolated lights can subtly change the natural character of rural areas like the North Pennines. While these changes can be difficult to notice, they can have a real impact on the natural environment.

Darkness plays an essential role in supporting wildlife. Many of the species that define the North Pennines, such as curlew, lapwing and woodcock, depend on natural night-time conditions to feed, breed and stay safe from predators. Bats hunt under cover of darkness, while countless insects and pollinators rely on the night to carry out their life cycles. When artificial light disrupts these patterns, it can alter behaviour and abundance in ways that ripple across entire ecosystems.

What’s becoming increasingly clear is that darkness is not just the absence of light, it is an important ecological resource in its own right. Natural light-dark cycles shape everything from migration and reproduction to predator-prey relationships. Even low levels of artificial lighting can influence these processes, affecting species in ways we are only just beginning to understand.

Some of the North Pennines’ champion species can be particularly sensitive to these changes. Atlantic salmon, for example, rely on natural day-night cycles to guide their movement through rivers, while amphibians, like the common toad, can experience disrupted breeding behaviour under artificial light. Maintaining dark river corridors and low-light environments around ponds can make a meaningful difference to these species.

The importance of darkness extends even further – to habitats and soils. Upland hay meadows, which are a characteristic habitat of the North Pennines and now nationally rare, depend on nocturnal pollinators to thrive. Artificial light can alter plant communities and disrupt the delicate balance that supports these species-rich grasslands. Even below ground, changes in light can affect soil health, influencing nutrients, carbon storage and the resilience of the landscape as a result.

Protecting dark skies in the North Pennines is therefore about much more than preserving a beautiful view of the stars. It is also about safeguarding the conditions that allow nature to function properly. By reducing unnecessary lighting and valuing the night as part of the natural environment, we have an opportunity to protect wildlife, strengthen ecosystems and support long-term nature recovery.

In a landscape rich in natural assets, darkness may be one of the most important, and overlooked, of all.

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