Ecological Impact of Artificial Light at Night: Effective Strategies and Measures to Deal with Protected Species and Habitats

Abstract

When conserving or protecting rare or endangered species, current general guidelines for reducing light pollution might not suffice to ensure long-term threatened species’ survival. Many protected areas are exposed to artificial light at levels with the potential to induce ecological impacts with unknown implications for the ecosystems they are designated to protect. Consequently, it is recommended that precautionary methods for the avoidance and mitigation of light pollution in protected areas be integrated into their management plans. This paper’s aims are to present an overview of best practices in precautionary methods to avoid and mitigate light pollution in protected areas and to identify and discuss what ecosystems should be considered light-sensitive and how to prioritise species and habitats that need protection from artificial light, including examples of legislation covering ecological light pollution in the European Union and in Sweden. The important aspects to include when considering light pollution at a landscape level are listed, and a proposal for prioritisation among species and habitats is suggested. Sensitive and conservation areas and important habitats for particularly vulnerable species could be prioritised for measures to minimise artificial lighting’s negative effects on biodiversity. This may be done by classifying protected natural environments into different zones and applying more constrained principles to limit lighting. The light pollution sensitivity of various environments and ecosystems suggests that different mitigation strategies and adaptations should be used depending on landscape characteristics, species sensitivity and other factors that may determine whether artificial light may be detrimental. Issues of the currently used measurement methods for artificial light at night are reviewed. We also propose and discuss the principles and benefits of using standardized measurement methods and appropriate instrumentation for field measurements of artificial light concerning the environmental impact of light pollution.

An Impact Analysis of Artificial Light at Night (ALAN) on Bats. A Case Study of the Historic Monument and Natura 2000 Wisłoujście Fortress in Gdansk, Poland

“…For epidemiological studies, some researchers believe that DMSP data should no longer be used [ 93 ]. Only one study could be identified that related to the ecological impact of ALAN that discussed general aspects of effective strategies and measures to deal with protected species and habitats [ 94 ].…”

Towards Insect-Friendly Road Lighting—A Transdisciplinary Multi-Stakeholder Approach Involving Citizen Scientists

“…Current environmental protection legislation lacks regulations for the protection of species and habitats from ALAN, especially those considered "normal", i.e., those without any special protection status, but which are equally important as food sources in the trophic system [68,69]. "Tatort Streetlight" is a citizen science project with the potential to establish and support regulations to reduce the adverse effects from road lighting on biodiversity and the night sky and to offer insect-friendly lighting solutions.…”

“…What our preliminary data do show is that road luminaires are attracting protected and common insect orders in high numbers. There is an urgent need to reduce the adverse effects of road lighting insects, although existing environmental protection regulations are insufficient tools in regards to outdoor lighting systems [68,69].…”

11 Pressing Research Questions on How Light Pollution Affects Biodiversity

“…Although lighting professionals (e.g., design and industry) increasingly acknowledge ALAN as a threat to biodiversity, there are diverging views regarding potential obstacles to light pollution mitigation (Schulte-Römer et al, 2019;Pérez Vega et al, 2021). Current technological advancements in outdoor lighting, particularly LEDs, in principle allow developing lighting mitigation strategies that balance conflicting interests between humans and biodiversity, but this potential remains largely untapped (Longcore, 2018;Bolliger et al, 2020;Deichmann et al, 2021;Jägerbrand and Bouroussis, 2021). Furthermore, LEDs are an energy efficient technology that promises net savings in energy consumption.…”