The new UK government is shining a more positive light on construction of on shore wind farms, but the potential impacts on wildlife (particularly bats and birds) can be negative if wind farms are created in unsuitable locations.
It’s making headline news as mortality events are increasingly recorded across the UK and worldwide. So what ecological factors need to be taken into account when deciding where to put a wind farm?
Here are our key recommendations when selecting and designing appropriate wind farm sites on purely ecological grounds (we’ll leave others to think about whether they’re actually windy or will have visual impacts etc).
Avoid sensitive landscapes
Primarily avoid those within an Impact Risk Zone (IRZ) of (i) a Special Protection Area (SPA), which is an area designated for its bird interest and therefore important for important for bird migration, breeding, wintering and/or feeding, or (ii) a Special Area of Conservation (SAC) for bats. These areas are especially valuable features of International importance. National Parks and Sites of Special Scientific Interest (SSSIs) are also protected areas that often support unique or vulnerable habitats and species of national importance.
Multi-Agency Geographic Information for the Countryside is an open-access resource you can use to find designated sites throughout the UK. The IRZ will change depending on the potential impacts and designated sites in question, however, searches typically start at a 10km radius from the site. Your ecologist will help you define this for your specific project.
Avoid sensitive habitats
In the UK, certain habitats are particularly sensitive and should generally be avoided when siting onshore wind farms. These areas are critical for biodiversity, support rare or endangered species, or have unique ecological characteristics that could be significantly impacted by wind farm development. Here are the key habitats to avoid:
Ancient woodlands: These are woodlands that have existed since at least 1600 AD. They are rich in biodiversity and contain complex ecosystems that have developed over centuries. Wind farm development could lead to the loss of irreplaceable habitats and species.
Mountain and moorland habitats: These often include sensitive ecosystems that are home to rare species like the golden eagle.
Rivers, marshes, and floodplains: These habitats support a wide range of wildlife, including migratory birds, amphibians, and invertebrates. Wind farms can disrupt water flow, alter hydrology, and fragment habitats, affecting the species that depend on these ecosystems.
Saltmarshes and coastal wetlands: These areas are crucial for birdlife, particularly as feeding and breeding grounds for waders and other bird species. They also provide important ecosystem services like flood protection and carbon storage.
Dune systems: Coastal dunes are dynamic habitats that support specialized flora and fauna. Disturbance from wind farm construction could lead to erosion and habitat loss.
Peat bogs and moors: Peatlands, including blanket bogs and raised bogs, are carbon-rich ecosystems that play a crucial role in carbon sequestration and support a range of specialized species. Disturbing these areas can release stored carbon, contributing to climate change, and degrade important wildlife habitats.
Heathlands: These are open habitats characterized by shrubs, particularly heather. Heathlands are home to many rare species and are sensitive to changes in land use. Wind farm construction could lead to habitat loss and fragmentation.
Species-rich grasslands: Species-rich habitats such as calcareous grassland can support a high diversity of plants, insects, and other wildlife. Wind farm development could lead to habitat degradation and loss of biodiversity.
Hang on…haven’t we mentioned just about every habitat type in the UK!? No, there are some which, in the right location can be slightly less harmful. For example, open arable habitat or pasture, and industrial areas can be suitable. Wind farms have successfully been created in some of the above habitats too, so their presence isn’t necessarily a deal-breaker with appropriate mitigation and site layout.
Identify baseline ecological value
Appoint an ecological consultancy to assess the potential ecological impacts of the wind farm, the access route and proposed cable route. Ecology by Design has substantial experience evaluating proposed sites and providing comprehensive reports to help with the decision-making process. We generally operate in central England, the south coast and into Wales. You can also find an ecologist using the CIEEM Registered Practices Directory.
A suite of surveys for protected and priority species is likely to be required over the course of a year to ensure the potential impacts on biodiversity can be identified. The most notable groups to be considered are bats and birds as they are aerial species which can directly be impacted by killing or injury during operation. However, terrestrial species such as great crested newts, reptiles, water vole and invertebrates may also be impacted during construction and, to a lesser extent, operation.
Assess potential impacts on biodiversity
Your ecologist will collate the survey data and identify potential impacts as a result of the proposals and the need for any mitigation, compensation or enhancement measures . This will ensure the development accords with best practice, legislation and planning policy in relation to Biodiversity Net Gain and protected and priority species. This is likely to include considering:
Biodiversity Net Gain: The statutory biodiversity metric will be used to identify biodiversity losses and gains as a result of the proposals and need for any habitat creation on or off-site to compensate for habitat losses and ensure a 10% gain is achieved.
Habitat loss and fragmentation: The construction of wind farms requires clearing land, which can lead to habitat loss and fragmentation for terrestrial species. Roads and infrastructure associated with wind farms can further fragment habitats, making it difficult for wildlife to move freely and access resources.
Noise: The noise generated by wind turbines can affect nearby wildlife.
Collision risk modelling: Birds and bats can collide with turbine blades, leading to fatalities. This is especially concerning for migratory species and those already at risk.
Habitat disruption: Wind farms can disrupt the natural habitats of birds and bats, particularly if placed in or near breeding, foraging, or roosting areas.
Behavioural changes: The presence of turbines can alter the behaviour of wildlife, potentially leading to avoidance of areas and disruption of feeding or mating patterns.
Invasive species: Disturbance of land during construction can facilitate the spread of invasive plant species, which can outcompete native vegetation and alter local ecosystems.
Cumulative impacts: When multiple wind farms are built in close proximity, the cumulative impact on habitats and wildlife corridors can be significant, exacerbating issues of habitat fragmentation.
Develop appropriate mitigation strategies
Site selection and layout: As detailed in Points (1) and (2) above, careful selection of wind farm sites and placement of turbines relative to important wildlife features such as woodland edge habitats, key wildlife habitats, migratory routes, and ecologically sensitive areas can reduce many of these impacts.
Technology improvements: Innovations such as bird-safe turbine designs, ultrasonic deterrents for bats, and quieter turbine models can mitigate some of the negative effects.
Environmental monitoring: Continuous monitoring of wildlife and ecosystems before, during, and after wind farm construction helps identify and address unforeseen impacts.
Adaptive management: Be prepared to adapt management practices based on monitoring results, including shutting down turbines during peak migration periods or adjusting turbine operation to reduce impacts on local wildlife, such as turning off turbines when wind speeds are low to reduce bat mortality.
Conclusion
While wind turbines offer a cleaner alternative to fossil fuels, they do have potential for ecological impacts that need careful management. Balancing renewable energy development with ecological interest in a given area requires thorough planning, ongoing research, and the implementation of mitigation strategies to minimise these impacts. Ecological consultancies such as Ecology by Design are there to help you navigate the process and secure the best outcomes for key stakeholders, energy generation and biodiversity.