Cambridge scientists raise concern new laws to protect nature won't work
Researchers have called for changes to the Government measures
Last updated 28th Jun 2024
There's concern laws around protecting our nature won't work according to Cambridge scientists.
Their new study's found no evidence that a Government planning policy - requiring a biodiversity net gain of at least 10% - will help birds or butterflies.
The University of Cambridge is making its own recommendations to the Government on how to improve the way it measures habitats and species.
"This is a good moment to turn that curve"
Dr Cicely Marshall is from the University's department of plant sciences and wrote the study:
"The whole law is about encouraging developers to think about their impact on nature and we're moving to this position where our expectation or the requirement is those developments are good for nature," she said.
"We're one of the most nature-depleted countries in the world; we've spent 100 years pushing our natural landscapes as far as they can go in terms of intensity production and urban development.
"This would be a good moment to turn that curve."
What is the study?
Researchers trialled a metric, used by the Government, to calculate the biodiversity value of 24 sites across England.
They found that plant biodiversity at the sites matched values produced using the metric, but bird and butterfly biodiversity did not.
Plants, birds and butterflies are used as indicators for the national state of nature and researchers say the metric must be improved to better capture the intricacies of the different species within an ecosystem.
The University of Cambridge says this is the first study based on the performance of the Department for Environment, Food and Rural Affairs' (Defra) statutory biodiversity metric across England.
The results of the study have been used to make recommendations to Defra and Natural England to help improve the metric.
What is the Government metric?
The Environment Act requires planning applications to demonstrate an overall biodiversity net gain of at least 10% as calculated using a statutory biodiversity metric.
That metric, introduced as part of the Environment Act, scores the condition and distinctiveness of a piece of land to calculate its biodiversity value in standardised biodiversity units.
This allows developers to project biodiversity losses and gains across a site, so they can ensure the development achieves a minimum 10% biodiversity gain.
Plans for biodiversity gain can involve replacing lost habitat with similar habitat - researchers say that nature recovery could be improved if the particular species and habitats impacted by a development were also taken into account in this process.
There can be vast differences in biodiversity across habitats such as croplands, and these aren’t captured by the metric which assigns all cropland the same condition score.
Study could help drive more money towards nature - experts
The researchers say the Government metric must be improved to better capture the intricacies of the different species within an ecosystem.
"Important nature recovery targets might be better connected green space, so animals can move around between patches of habitat that are important to them, or making space for species that haven't done so well in landscapes over the last 50-100 years," Dr Marshall said.
“At the moment, the metric does capture plant diversity quite well, but it doesn’t reflect the intricacies of ecosystems – species like birds and butterflies use habitats in very different ways.
"It has the potential to push a lot of money from developers into nature conservation; it's our responsibility as conservationists to make sure we're targeting that policy as closely to the targets of nature recovery we want to see as we can."