Airports can impact biodiversity in a number of ways, including loss or degradation of habitats when airports and airfields expand, deterring or controlling wildlife for operational reasons, and through the effects of light and noise pollution on some species. A list of biodiversity indicators is published and maintained by the Government.
With over 2000 bird strikes recorded annually in the UK, bird populations are treated as hazards around airports and are controlled accordingly. However, caution about bird populations extends well beyond the immediate vicinity of an airport – the CAA advises that steps should be considered to minimise bird populations as far as ten miles away.
Reducing the attractiveness of surrounding areas to large birds – for example by removing trees or other nesting habitat, or using noise and flare guns – can impinge on other wildlife populations. In addition, the law allows Natural England to issue licences to airports to control a range of bird species within an area 13 kilometres from the airport boundary, by shooting them, or by destroying nests or eggs. The range of species that can be controlled in this way includes some threatened species, such as curlews and herring gulls, if an airport perceives that there is a safety issue.
Biodiversity matters because it supports the vital benefits humans get from the natural environment. It contributes to the economy, health and well-being, and it enriches our lives.UK Biodiversity indicators 2020
The biodiversity impacts of aviation are usually addressed in the context of airport planning applications, and environmental assessments should identify sensitive habitats, any risks, and appropriate mitigation. Examples of mitigation include re-creation of habitats elsewhere to provide a home for flora and fauna, or the diversion of watercourses. In some cases, the significance of likely biodiversity impacts can delay or stop expansion. In the 1990s, planning permission for a development at Lydd Airport was delayed while investigations took place into the impact of aircraft noise on the breeding success of birds at the adjacent internationally protected wetlands.
Some airports, such as Heathrow and Gatwick, are keen to promote their biodiversity projects located in wildlife areas around the airports. However, in the context of noise and light pollution from commercial aircraft operations, the effectiveness of these projects in helping to halt the decline of biodiversity in the UK, or even locally, is far from clear.
Birds, amphibians, invertebrates, fish, mammals and reptiles can be very sensitive to noise and light pollution. Studies have shown that even low levels of human noise disturbance can severely impact the ability of animals to communicate and breed. Light pollution harms biodiversity by interfering with natural day-night rhythms and night habits, affecting the reproduction, feeding, and migration cycles of many different animal groups. Artificial lighting can confuse migratory birds, depleting their energy sources and threatening their survival rates. By extending the hunting time of daytime feeders, light pollution can also lead to over-predation of some nocturnal species. When combined, noise and light pollution – from roads, shipping, urban sprawl as well as from aviation – can throw the lives of animal populations worryingly out of balance.
Adopting a siloed approach to reversing biodiversity has been ineffective. As the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) concluded in its June 2021 report:
Biodiversity loss and climate change are both driven by human economic activities and mutually reinforce each other” This being the case, both of these environmental impacts must be tackled simultaneously – and urgently.