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. In some cases, the significance of likely biodiversity impacts has delayed airport expansion applications. As an example, planning permission for a development at Lydd Airport in the 1990s was delayed while investigations took place into the impact of aircraft noise on the breeding success of birds at the adjacent internationally protected wetlands.
The Environment Act (2021), which aims to strengthen biodiversity protections with the planning system, made biodiversity net gain (on site, offsite or via purchasing biodiversity credits) a condition of planning permissions and development consents in England. Developers must be able to show that proposals will achieve a 10% net increase in biodiversity against a baseline (using a net gain toolkit). However, net gain effectively trades current losses in habitat area for promises of uncertain gains in habitat quality in the future (newly created habitats can take 30 years to mature). Questions have been raised about how net gain will be monitored and regulated.
Meanwhile, some airport expansion plans risk harm to highly sensitive wildlife sites. For example, the Oglet Shore on the River Mersey is a RAMSAR site and a designated Site of Special Scientific Interest, but it is also adjacent to Liverpool John Lennon Airport which is planning to expand. Local people fear that the airport’s ambitions for growth will cause considerable harm to Oglet Shore’s ecosystem, and there is little confidence that the planning system will afford the site the necessary protections.
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.
AEF is not persuaded that the Government can reconcile its continued support for environmentally damaging airport expansion with it ambitions to improve and enhance the natural world in areas surrounding airports.
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.