For some news outside of Asia, conservation practitioners in the UK and beyond are raising serious concerns about the Biodiversity Net Gain (BNG) Metric 3.0 which was recently published by Natural England in July 2021. The Biodiversity Net Gain metric involves calculations of the difference between pre-development and post-development (e.g. for new housing or roads), with the goal of leaving the natural environmental in a measurably better state. BNG policies aims to ensure new development avoids harm in the first place, or compensates for losses with net gains elsewhere.

The BNG is a right concept and principle, however, its complicated assessment process is difficult to operationalize, and critical habitats are excluded or categorized as “undesirable” or “low value” in the metric such as scrubland, sand quarries and field margins. Critics pointed out that one of the most well-regarded re-wilding projects in English, the Knepp estate would score low on the metric – a site which is home to critically endangered species including the nightingale and turtle dove.

Sophus zu Ermgassen, an ecological economist at the University of Kent stated that the metric was designed with “very traditional conservation management in mind”.

Additionally, developments have been pushed through under the scheme which have led to a real-time reduction in green space, offset by promises of increases in small, but more ecologically habitats in the future – according to Ermgassen, essentially “trading wildlife losses today for uncertain future gains”.

“There are really good academics, developers, NGOs and government officials working on net gain throughout the UK. The country has decent governance, and one of the most decrepit biodiversity baselines there is, so if we can’t make it work here it probably can’t work anywhere,” Ermgassen added.

Moreover, most of biodiversity samples […]