Is Earth Law a Solution to Light Pollution?

Photo by Rachel Tang

Photo by Rachel Tang

By Rachel Tang

Background and Introduction

When people talk about the city of Hong Kong, what do you think of? It might be the food, or perhaps the city’s dazzling lights shining out across the Victoria Harbour at night. 

Research conducted by the University of Hong Kong’s “HK Night Sky Brightness Monitoring Network” showed that Tsim Sha Tsui, a busy shopping district next to the Victoria Harbour, shines 1200 times brighter than the International Astronomical Union standard from 8:30pm to 11pm [1]. Compare this to European cities where readings are normally below 100 times the standard, one tenth of Hong Kong’s wattage [2]. People living near intensely light polluted areas have reported that they were sleep deprived, suffered from insomnia or that they experienced a reduction in sleep quality [3].

You might think that this only happens in Hong Kong’s business and tourism district, but statistics say otherwise. Even rural night skies are too bright. Wetland Park lights in Tin Shui Wai measured 130 times the standard [4]. At the Astropark stargazing facility near High Island Reservoir, where it is supposed to be the darkest, the brightness exceeded the standard by 20 times [5]. This bleed of light pollution into rural areas also happens on a global level in most large cities such as London and New York.

How does light pollution affect wildlife?

Earth’s animal and plant community evolved under an unpolluted night sky and uses the rhythms of moonlight to regulate many of its systems. Ecologists face difficulties in accurately measuring light and observing how it causes change in different species, but initial results have shown how night lights exert stress on the ecosystem.

Steve Long, a plant biologist at the University of Illinois at Urbana stated, “We know a great deal now about the impacts of rising CO₂, but how extensive are the impacts of light pollution? We’re gambling with our future in what we’re doing to the environment" [6]. Humankind’s artificial lights disturb the environments animals and plants have evolved to live in. Here are some telling examples of the ecological effects of light pollution:

Short-tailed fruit bat. Photo by Andy Morffew

Short-tailed fruit bat. Photo by Andy Morffew

  • Short-tailed fruit bats are forced to limit activity to less-illuminated regions. Pepper plants rely on bats to disperse pepper seeds to other parts of the forest. This allows the plants to minimize the competition for nutrients within their species. However, this natural process is deterred by the artificial lights [7]. In addition, less bats also means a reduction in the pollination of flowers of tropical and subtropical plants. A reduction in fruit bat activity limits forest regeneration and timber production [8].

  • Birds are often distracted by commercial lights, resulting in fatal collisions with windows. Birds that migrate at night often become confused by the lights and separate from their flock, lowering their survival chances, says Dr Pun Chun-shing Jason, a research scientist at HKU [9]. With fewer birds, it impacts the food chain: more insects and fruits survive as less of them are consumed by birds. There might also be a reduction in the number of owls, eagles and other predators that eat birds as a primary food source, upsetting the balance of nature. Songbirds are also disrupted. Songbirds rely on their singing to attract mating partners. Research shows that artificial night light contributes greatly to a change in birdsong behavior, leading to birds starting their dawn singing earlier [10].

  • Fireflies are also affected by artificial lights. Rural areas like Wetland Park receive intense light disruption, causing the insects to confuse artificial lights with the moon which can prevent fireflies from navigating their environment effectively. The lights may also impact fireflies' breeding as they rely on light signals for mating, says Yiu Vor, Chairman of the Hong Kong Entomological Society [11]. As fireflies consume the larvae of snails and slugs, a decrease in fireflies will result in increased populations of these creatures. It may also reduce the population of firefly predators such as frogs, toads, bats and mice.

What can we do? What can wild creatures do?

Night sky in Yosemite, California. Photo by Casey Horner

Night sky in Yosemite, California. Photo by Casey Horner

Human residents can voice concerns about the way light pollution affects their natural rhythms. Residents may file complaints against the responsible company or bring it to the courts through litigation, for instance suing for damages suffered in terms of health due to the light pollution. They may also file complaints to the Environmental Protection Department, which received “337 complaints about light pollution, mainly about lighting from shops and signboards – up from 256 in 2015, and 229 in 2014” [12]. 

Humans have their rights and this should be respected. But humans are not the only species suffering. What about the wildlife which are suffering from the unnecessarily excessive lights? How can they fight back against the injustice?

Earth Law grants nature the right to enforce her inherent right and status in court (learn more about Earth Law here). This legal principle also enable citizens to enforce that right when they witness such an injustice. Therefore if rights of nature is allowed, the law can effectively permit the planet to have a “voice” in court and fight against her suffering. 

Causes of Resistance to Change in Hong Kong

Why is the problem so severe in Hong Kong? Unlike in other major cities, there is no legislation regulating external lighting in the city. The only regulation in Hong Kong is the Guidelines on Industry Best Practices for External Lighting Installations, a voluntary charter inviting businesses to switch off outdoor lighting from 11pm to 7am. The charter does not apply to security and decorations during festive seasons like Christmas or Chinese New Year, minimizing its effectiveness. Roy Tam Hoi-pong, chief of Green Sense commented that “the pledge is not strict enough”, and that the government is not prioritizing the issue. Green Sense and other groups have “asked for legislation for 10 years” with no relevant governmental actions yet in place [13]. 

Therefore, in a global financial centre like Hong Kong, businesses make the best use of signage, billboards and external lighting for advertisement purposes under no strict legal enforcement. Last October, a massive full-HD LED screen was unveiled on the external wall of Sogo Department Store, Causeway Bay [14]. The screen is the size of five tennis courts, totaling 19 x 72 meters and claiming a throne as one of the largest LED billboards in the Asia-Pacific region [15]. Tanya Chan, a Civic Party lawmaker, stated that large LED billboards will increase the surrounding temperature and impact the environment [16].

As an eminent tourist city, Hong Kong relies on its signature nighttime views to generate and facilitate the tourism industry. The glamorous night view of the Victoria Harbour and Victoria Peak would be like any other riverside and mountain top without the lights radiating from the skyscrapers. As a city known for its nighttime cityscape, it will notably damage the tourism industry if the city implemented laws to restrict external light emission. This is particularly true during festivals like Christmas or Lunar New Year, where at least “50 per cent of public and commercial buildings in Tsim Sha Tsui have Christmas lights on their exteriors." Light festivals such as A Symphony of Lights feature installations and new LED boards which consume less energy, attracting tourists and local visitors. However, despite conserving energy, which may reduce the environmental damage, the light itself still impacts the wildlife and the sky [17].

Perhaps, a difficulty for the government is the strong commercial pressure against the imposition of light pollution restrictions. As both the tourism and business industries comprise major sectors of Hong Kong’s economy, the government may give them preferential treatment. The government showed itself unwilling to act in response to a question raised by Hon Priscilla Leung in the Legislative Council; the government wanted to resort to a looser regulation on light pollution, most possibly to steer clear of conflicts with the commercial sector [18].

Another restraint may be due to the city’s landscape mapping. As Hong Kong has merged zones of commercial and residential areas in most districts, it is difficult to enforce laws which apply different levels of regulation to different types of land use [19].

Learning from other cities

Hong Kong is in reality an outlier from other major cities in terms of legislation governing the control of external lights. Although some work has been already been done in Hong Kong, such as implementing the voluntary charter and guidelines, but tougher measures are necessary to effectively curb light pollution.

Similar to Hong Kong, Shanghai in China is also well-known for its vibrant night view at the Bund, the western bank of Huangpu River. But recent legislation sets out that night lights should not affect the “normal living of nearby residents” carrying a legal consequence of 1000-yuan-fine (equivalent to USD160), making Shanghai one of the cities with the most anti-light pollution laws in Asia [20].

Guo Hua, Director of the Bureau's Lights and Advertisements Administration Department, Shanghai local government, said that with the new policy, “the brightness of lights in the downtown commercial district will be reduced and the frequency of lights flashing will also be reduced” [21].

Businesses are therefore limited by the legal enforcement and people have become more aware of the issue’s severity. However, most of Shanghai’s emphasis is to provide an improved environment for the sake of human health; more attention should be placed by the government on the consequences imposed on the wildlife. Similar legal fines and punishments have been put in place in the recent decades across the globe, including in Paris and Sydney.

Artificial lights as seen by NASA satellites

Artificial lights as seen by NASA satellites


Efforts should be taken by the government to implement suitable policies with legal enforcements to ensure their efficiency. The government should not fear commercial pressure, and should not sacrifice wildlife and nature to fulfill commercial industry’s preferences. 

Other legislation should be considered in addition to legal punishments limiting illumination during certain periods of the day. For instance, long wavelength (red light) outdoor lights may reduce the number of sea turtle hatchlings mistaking lights for the moon’s reflection on the sea. The law can be designed to limit short-wavelength-lights near coastal areas to protect the rights of the hatchlings [22].

You may be questioning the government’s willingness to take action. But, instead of merely waiting for a governmental move, you can take part to make a change. Social pressure often works as effectively and even more effectively. By making individual requests to large businesses to change their external lighting practices we can make them understand that they risk boycotts from consumers if they do not make changes to their harmful practices and improve. 

Hong Kong can also take inspiration from the cities with laws governing light pollution. However, much of the governmental concern in these cities, hence their policies, are aimed at protecting neighbouring residents’ health and the conservation of energy. Not much attention has been directed at the wildlife and nature that should enjoy its rights as much as humans do. Introducing Earth law to Hong Kong, new to the jurisdiction, may be a solution to solve such problems in the long run. 

As briefly mentioned above, Earth law grants nature the right to enforce her rights in court and for citizens to enforce on behalf of nature. Earth law puts ecosystem rights at the front of the conversation. It enables the public’s direct action and puts legal pressure on the government and the public to face up to the severe environmental issues in Hong Kong and around the world right now. Rights of nature should be granted as the most effective way to return the power over light and darkness to nature.

What you can do to help

  • Minimize use of lights, especially during day time (utilize natural light!)

  • Use glare-free (coloured) lights — yellow, red or amber lights

  • Use bright-sensor or motion-sensor lights

  • Use covered bulbs and place them facing downwards, avoiding excessive light reflections in the sky [23]

Take action now!