Solar farms can be wildlife havens

solar panels and wildlife

A report from Solar Energy UK has found that solar farms are home to many declining species.

The report, Solar Habitat: Ecological trends on solar farms in the UK, states that linnets, a bird on the UK’s red list of conservation concern, were found across more than half of the 37 solar farms in the initial survey last year. Numbers of the small finch species have fallen dramatically since the 1960s, thought to be linked to the intensification of agriculture.

Yellowhammers and skylarks, which have the same status, were also found on around half of the sites surveyed, with grey wagtails, whitethroats, wrens and willow warblers, all amber listed by the British Trust for Ornithology, also among the birds noted by ecologists.

The report was produced with Lancaster University and consultancies Clarkson & Woods and Wychwood Biodiversity.

Hollie Blaydes, the PhD student who led the research, said:

It is very clear that solar farms can be wildlife havens. About half of solar farms are managed with conservation specifically in mind, such as limiting grazing to only certain times of the year and reducing herbicide use. It’s on these where wildlife can really thrive and benefit from the habitats created. These findings and the net gain regime could help tilt the industry further towards improving biodiversity.

The most encountered mammals were brown hares, on a quarter of the sites surveyed.

As the report states, “The low intensity of management on solar farms, as well as the range of habitats present, can support a variety of invertebrate species,” upon which many others ultimately depend, either for food or pollination. Nine of the sites were home to the small heath butterfly, a species of principal importance under the Natural Environment and Rural Communities Act 2006 that has declined recently. The more widespread but declining cinnabar moth, a species of conservation concern, was recorded on seven sites.

The report considers why some solar farms are more biodiverse than others, finding that the diversity and number of invertebrates were strongly associated with management being more focused on wildlife. This would include not using herbicides, providing a variety of habitats and seasonal rather than year-round grazing. Almost all sites (94%) had some conservation measures, graded 2-3 on a 1-5 scale, where one is optimal.

The report indicates that solar farms may provide a “significant resource for invertebrates”, due to the vast amount of nectar they can produce: more than two tonnes a year, according to an estimate for one site. Unsurprisingly, solar farms with greater nectar productivity accommodated significantly more butterflies and bees, in abundance and species richness. As nectar resources in surrounding arable or pastureland may provide nectar for only a short time before, “solar farms may offer a longer-term resource supporting larger numbers of local pollinators which may, in turn, enhance pollination services to nearby crops,” the report concludes.

The report includes two case studies of best practice: successfully attracting the cirl bunting – the UK’s rarest resident farmland bird – to the Sawmills solar farm in Devon and another illustrating solar farms’ potential for creating biodiversity net gain, offsetting the damage to nature caused by other developments.

Rachel Hayes, Consents and ESG Policy Manager at Solar Energy UK, said:

This report confirms what we have known anecdotally for many years: well-designed and well-managed solar farms can help address the climate emergency and loss of biodiversity in the UK.

Wildlife can benefit hugely from developing solar farms, providing a variety of habitats and raising the numbers of some of our most threatened species while pushing us forward towards net zero. I hope that the report’s findings will encourage more asset owners to adopt the standardised approach to monitoring ecology on solar farms and make the results even more robust.