No evidence that England’s new ‘biodiversity boost’ planning policy will help birds or butterflies

A new legal requirement in the UK's Environment Act mandates that planning applications must demonstrate a biodiversity net gain of at least 10% starting in 2024, using a new statutory biodiversity metric. Researchers at the University of Cambridge evaluated this metric across 24 sites in England, comparing it against long-term biodiversity data. They found that while plant biodiversity values matched the metric's results, bird and butterfly biodiversity did not, suggesting that the metric may not lead to real-life gains for these species without additional conservation efforts.

Dr. Cicely Marshall, the study's lead author, emphasized the need for improvements in the metric to better capture the complexities of different ecosystems. The study's findings, published in the Journal of Applied Ecology, recommend enhancing the metric to consider specific species and habitat impacts, as current scores for habitats like cropland do not reflect their varied ecological values. These improvements could ensure that the significant funding directed towards biodiversity conservation from development projects, estimated to be worth £135m-£274m annually, truly benefits nature recovery in England.

Read the full study in the Journal of Applied Ecology.