UK Biodiversity Net Gain algorithm accused of not being fit for purpose

A UK biodiversity algorithm was accused of being inaccurate, unreliable and easy to manipulate.

Biodiversity Net Gain (BNG), a biodiversity metric for new developments introduced in the UK government's 2021 Environment Bill, was intended to determine how new houses, roads, and other construction projects must achieve no net loss of biodiversity, or, if nature is damaged on the construction site, achieve a 10 percent net gain elsewhere.

However, BNG was found not to value scrubby landscapes such as sand pits or those used for rewilding programmes, which it logged as a sign of 'degradation' and would not therefore qualify for compensation, resulting in complaints from academics and conservationists that the system was not fit for purpose. 

The UK government has a target of building 300,000 new homes a year by the mid-2020s.