Advocating for 20% Biodiversity
Net Gain (BNG)

Developing an evidence base for Biodiversity Net Gain (BNG) targets of greater than 10%.

Snake's head fritillary flowers growing wild with other spring flowers in Fellows' Garden, accessed from Magdelen Meadow Oxford, Oxfordshire UK. The purple chequered flowers are rare and endangered.


New legislation introduced by the Environment Act (2021) requires developers to demonstrate a minumum of 10% net gain in biodiversity in order to gain planning permission. This new Biodiversity Net Gain (BNG) legislation has the potential to bring benefits to wildlife in Oxfordshire if implemented effectively.

What we're doing

We commissioned the development of an evidence base that can be used by Local Planning Authorities who decide to make developers deliver a net gain of greater than 10%.

The report found that Oxfordshire is highly nature-depleted, with far lower proportions of priority habitats and protected areas than the average for England as a whole. Also, the remaining semi-natural habitats in the county are at risk of further loss and fragmentation due to development. It concluded that the national minimum target of 10% BNG will not be sufficient to reverse the historic losses caused by development during the current local plan periods, and make a meaningful contribution to delivering the national and local biodiversity targets for 2030. Other councils in a similar position have also selected higher targets, e.g. 20% in Surrey. Even higher targets could be needed to be confident that genuine gains will be delivered, when the governance issues associated with delivering on-site habitats are taken into account.

We are using this evidence base to advocate for Local Planning Authorities to implement a higher target than the 10% minimum where possible.