Biological – threat to biodiversity

–    Catherine Rich and Travis Longcore (eds.), Ecological Consequences of Artificial Night Lighting, Island Press, Washington, DC: 2006.
–    Travis Longcore and Catherine Rich, ‘Ecological Light Pollution’, (2004) 2(4) Front Ecol Environ 191-8.
–    Starlight Theatre, Light Pollution and Animal Behaviour
–    Sándor Boldogh, Dénes Dobrosi And Péter Samu, ‘The effects of the illumination of buildings on house-dwelling bats and its conservation consequences’, (2007) Acta Chiropterologica 9(2): 527–534.
–    P. Deda, I. Elbertzhagen, M. Klussmann,  Light pollution and the impacts on biodiversity, species and their habitats, Secretariat of the Convention on the Conservation of Migratory Species of Wild Animals (UNEP-CMS)
–    Marianne V. Moore, Stephanie M. Pierce, Hannah M. Walsh, Siri K. Kvalvik and Julie D. Lim, ‘Urban light pollution alters the diel vertical migration of Daphnia’, (2000) Verh. Internat. Verein. Limnol. 27: 1-4.


Health – threat to human health

–    Kerenyi, N A, Pandula, E, Feuer, G, ‘Why the incidence of cancer is increasing: the role of ‘light pollution”, (1990) Med-Hypotheses 33(2): 75-8.
–    Siegelová J., Fišer B., Brázdová Z., Forejt M., Homo lka P., Vank P., Havelková A., Hollan J., Cornelissen G., Halberg F., ‘Disturbance of circadian rhythm in blood pressure by lack of darkness at night’ (2006) Scripta Medica (Brno) 79 (3): 147–154.
–    E. S. O’Leary, E. R. Schoenfeld, R. G. Stevens, G. C. Kabat, K. Henderson, R. Grimson, M. D. Gammon, M. C. Leske, ‘Shift Work, Light at Night, and Breast Cancer on Long Island, New York’ (2006) Am. J. Epidemiol. 164(4): 358 – 366.
–    Hansen, J., ‘Light at Night, Shiftwork, and Breast Cancer Risk’ (2001) Journal of the National Cancer Institute 93(20): 1513-1515.


Cultural and natural heritage – hindering enjoyment of nature


Energy inefficiency – waste of energy contributing to climate change

S.I. Isobe and S. Hamamura, Light Pollution and its Energy Loss (2000) Astrophysics and Space Science 273: 289-294.






–    Fully shielded lighting both in cities and rural areas. Redirecting light down only to where it is needed reduces the unnecessary spill of light and the required lamp wattage.

–    Use of low- or high-pressure sodium lighting with the orange component instead of the mercury lamps or metal halide discharge lamps with the enhanced blue / bluish component. The enhanced blue part of the spectrum is visible by more animal species and humans.

–    Reducing the levels of illumination of lights at night or turning them off when these are not needed (dimming).

–    Limitation on illumination of surfaces (outdoor advertising signs, billboards, facades, decorative lighting etc.).

–    Sensible spatial planning. Public lighting is not necessarily needed on each parking lot, in rural areas or on roads intended only for use of vehicles.

–    Laws, not voluntary reductions are needed. Self-regulation is likely to not be effective against the comercial interests, capital or ignorance.


Problems of light pollution:



Cultural and natural heritage



Light pollution as a threat to biodiversity

A biological rhytm of day and night is natural to several species, habitats and ecosystems and indispensable for a healthy funcitoning of the biosphere. Artificial light affects the growth of plants and their resistance to infestations and disease, and influences the growth, feeding, reproduction and migration patterns of a number of animals.

Although more ecological impacts of light pollution are expected to be known as the research in the field progresses, sufficient evidence exists about the importance of darkness for a number of animal and plant species. It is our responsibility to protect them, especially if the solutions are simple.


Light pollution as a threat to human health

The biological rhytm of day-light and darkness is natural also to humans and thus vital to our health. By suppressing melatonin production and interfering with the circadian rhythms, intrusive street lighting entering into bedrooms at night may lead to sleep deprivation, depression and impaired thinking. Research has shown that long-lasting increase of systolic blood pressure could be linked with an increase of risk of cardiovascular diseases like stroke and myocardial infarction. High night-light intensity has also been associated with the higher incidence of breast cancer, pointing to the possibility that exposure to light at night may be the most powerful factor in breast cancer besides genetic defects.

Although further research is needed health effects demonstrated so far are alarming enough to urge a response.


Light pollution hinders enjoyment of (nocturnal) nature

Artificial skyglow is becoming an ever more serious hindrance to enjoyment of the starlight and astronomical research. Professional astronomy as it has been developing over the past centuries is a key to understanding our world. Not only scientists, each individual has a right to an unpolluted night sky that has a aesthetic, cultural and spiritual value.

These and many more values of pristine night sky have been recognised in the Declaration in Defense of the Night Sky and the Right to Starlight, adopted in La Palma in 2007. Among others, protected areas are “called to include the protection of clear night skies as a key factor strenghtening their mission.”

Mariborsko pohorje

Light pollution is a waste of energy and considerably contributes to climate change

Unshielded lighting emits up to 50% of light in the sky. Production of this unnecessary energy has considerable economic and environmental impacts. These are greatly at odds with the efforts to reduce energy inefficiency and greenhouse gas emissions.

Avoiding light pollution is not only an ecologically but also economically viable solution. Finally, only ecological outdoor lighting is consisent with the principles of sustainable development.



Useful links

Starlight Initiative

Dark Skies Awareness

International Dark-sky Association

Convention on Migratory Species, Light pollution is increasing threat to migratory wildlife

Ramsar Convention

Starlight Theatre, Light pollution – a guide for your personal campaign

National Geographic, the issue on light pollution


Annual European Symposia for the Protection of the Night Sky

2010: 10th European Symposium for the Protection of the Night Sky, Kaposvar, Hungary

2009: 9th European Symposium for the Protection of the Night Sky, Armagh, Ireland

2008: 8th European Symposium for the Protection of the Night Sky, Vienna, Austria

2007: 7th European Symposium for the Protection of the Night Sky, Bled, Slovenia

2006: 6th European Symposium for the Protection of the Night Sky, Portsmouth, England, UK

2005: 5th European Symposium for the Protection of the Night Sky, Genk, Belgium

2004: 4th European Symposium for the Protection of the Night Sky, Paris, France

2003: 3rd European Symposium for the Protection of the Night Sky, Stuttgart, Germany

2002: 2nd European Symposium for the Protection of the Night Sky, Luzern, Switzerland

1998: 1st European Symposium for the Protection of the Night Sky, Paris, France


1st Dark-sky Camp at Lastovo island, Croatia

About us

Initiative for an international association of dark-sky parks is a network of inidividuals and groups that work to reduce light pollution in their respective countries. The initiative is coordinated from Slovenia, being the first country to have a strong light pollution law in force on a nation-wide level.

We take concrete actions to halt growth of light pollution on a wider scale. Our activities range from lobbying for and participating at the drafting of the legislation to awareness raising, research, cooperation with the producers of quality ecological lighting and monitoring of light pollution. We believe that by working together we gain the power to mobilise people from all over the world to stop this one form of pollution from causing irreverable effects.

We invite management of protected areas and other responsible individuals to join our efforts.

About us

Why the Initiative?

Why an organisation?

Why international?

Why protected areas?

The problems are urgent.

Why an organisation?

Light pollution will not be reduced by voluntary work as lack of time and commitment is a likely impediment. Professionals are needed to implement the known solutions. We recommend that these are part of a larger network which offers them opportunities to share experience and best practices, provides them with capacity building opportunities and motivates them.

Why international?

Light travells up to 200 km in the horizontal direction. Light crosses the borders of individual countries and regions, and therefore cooperation is needed. Much artificial skyglow could be avoided by stopping unused waste light from travelling at or just above the horizontal.

Why protected areas?

Protected areas are established and managed with a purpose of protecting and maintaining biological diversity, and natural and associated cultural resources; which must be effectively managed through legal and other means. Light pollution is a threat to the purpose of protected areas. Management of parks is therefore responsible to address it. Protected areas must identify processes that threaten their conservationist activities and must promote environmentally sound means to reduce them.


The problems are urgent

–    Over the last decades, the degree and intensity of light pollution has been growing exponentially and is still increasing every year by around 5-8%, depending on the country.

–    Once outdoor lighting is installed its removal is unlikely. As it is the case with environmental problems generally, preventative action is preferable also when dealing with light pollution.

–    No international agreement is in place to oblige countries to reduce solely light pollution; individual action depends on the forward-thinking attitude.

–    Light pollution is one of the rare reversable environmental problems. A positive action in the field would boost the confidence of the citizens in the ability to solve environmental problems.


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