More than 50 wildlife experts, politicians and celebrities have signed a letter to Boris Johnson demanding tougher action on nature loss.
The UK prime minister’s father, Stanley, is among signatories calling on the UK to become the first country to set legally binding targets for nature recovery.
The government has pledged to protect 30% of land and sea for nature by 2030.
The letter calls for this ambition to be enshrined in law.
The UK is one of the most nature-depleted countries in Europe. Half of UK wildlife has decreased since 1970, with one in seven species now at risk of extinction. Rivers and lakes are in a poor state, due to pollution and sewage.
The open letter is signed by nature groups, from The Wildlife Trusts and the RSPB, to nature campaigners such as Chris Packham, Mya-Rose Craig and Dara McAnulty.
It says the Environment Bill “falls short of its potential to set world-leading nature targets”, and the framework for target-setting is “too technocratic and slow”.
The letter states: “Just as the UK led the way in creating the world’s first Climate Change Act, we can be the first country to set ambitious targets in law for the recovery of the natural world.”
And it concludes that a “mismatch in urgency and timescales” means that the PM’s commitment to protect and manage 30% of land and seas for nature by 2030 cannot be placed in law under the Environment Bill framework.
Beccy Speight, chief executive of the RSPB, said: “Nature in the UK is in freefall – we are losing species and the habitat they need every year. Actions not just words are now required.”
Dr Richard Benwell, the chief executive of Wildlife and Countryside Link, added: “First and foremost, we need a powerful target to improve the state of nature in the Environment Bill to ensure the government plays its part in protecting our natural world.”
The Environment Bill, which has been delayed in Parliament for a third time, is expected to begin progress again through the House of Lords in May.
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