Experts fear the implementation of the EU nature directives could be watered down and enforcement weakened once the UK has left the EU.
While the Habitats Directive protects important sites of habitats and specific species such as the great crested newt, the Birds Directive protects all wild birds in the EU, including their eggs, nests and habitats. Together, these directives underpin the Natura 2000 network – a haven for Europe's most valuable habitats and threatened species that encompasses 18% of the EU’s land area and almost 6% of its marine territory.
To date, Natura 2000 sites cover 17,245,900 hectares of land and marine habitat in the UK, made up of 655 special areas of conservation (SACs) and 275 special protection areas (SPAs).
According to Kate Jennings, RSPB’s head of site conservation policy, there is “rock-solid evidence” that these protected spaces work.
“RSPB scientists have shown that [EU-protected bird species] do better in countries that have SPAs than in countries that don’t. These birds do better in countries that have more and bigger SPAs... and they have done better in countries that have been inside the EU longer.
“In other words, the longer you have the Birds Directive applying, the better those birds have done,” she said.
So what does the future hold for these EU-protected sites once the UK has left the EU?
For its part, Natural England says the same legal protections for SACs and SPAs will be upheld in the UK after Brexit because both designations contribute to the achievement of domestic and international biodiversity objectives. These include international agreements such as the 1979 Berne Convention, which established a pan-European network of protected sites known as the emerald network of areas of special conservation interest (ASCIs).
But not everyone is convinced international conventions hold much water.
“Anyone who thinks they will be able to provide the same protections as the nature directives are living in a fantasy world,” said Donald McGillivray, professor of environmental law at Sussex University.
McGillivray believes the problems of the “toothless” Berne Convention and other international biodiversity treaties is that they lack the “enforcement machinery that you get in the European court system”.
For example, McGillivray underscores the high-profile case of Greece and the endangered turtle (C-103/00 Commission v. Hellenic Republic  ECR I-1147).
The dispute arose because tourism-related development was harming the breeding behaviour of the endangered loggerhead turtles. While parties of the Berne Convention tried to hold Greece accountable, without access to a court system they were powerless to change the country’s position, said McGillivray. It was not until the Habitats Directive came into force in 1992 that Greece was challenged again and forced to remedy the situation by the European courts.
“None of the biodiversity conventions have a court or tribunal structure attached to them, they operate by political pressure,” McGillivray said.
The manner in which member states implement directives hinges on guidance, which is a matter of national policy. But no one outside Downing Street knows whether DEFRA will tighten or loosen its approach.
DEFRA is currently working on new guidance, according to Jennings. “Moving forward, it’s really important we get guidance really quickly, so that everyone understands [the regulations] crystal clear,” she said.
For now, DEFRA’s statutory instruments will have to suffice. The Conservation of Habitats and Species (Amendment) (EU Exit) Regulations 2019 pull current environmental regulations underpinned by EU law across into national law, known as the EU operability regulations, said Jennings.
The first post-Brexit test of enforcement of the nature directives could take place over the Solent and Dorset Coast SPA and SAC.
For developers, the Solent and its EU-protected sites have become synonymous with the nitrates crisis. Since June last year, local planning authorities in south Hampshire have been unwilling to grant planning permissions for up to 10,000 homes after legal advice from Natural England required residential applications to guarantee they will not increase nitrate pressure on the sensitive sites.
Prime minister Boris Johnson intervened this month, vowing to settle the nitrates crisis with a ministerial ‘Dyno-Rod’ but did not divulge any more details.
According to Richard Kimblin QC, from No5 Barristers Chambers, how this ‘Dyno-Rod’ is used will be a key litmus test for how EU-protected sites will be treated after Brexit.
“We can see straight away that nitrate and phosphate impacts on important habitats, which are presently causing such difficulties for planning authorities, will change from policing by the European Commission to a new mechanism.
“The ability to call the government to account for failures to provide the protections under each directive is going to be the first big test. It is a real change from powers for the commission to impose very substantial fines to a system which is presently ill-defined,” he said.
The Office for Environmental Protection (OEP) is the proposed regulatory body that will take on some of the European Commission’s oversight and enforcement functions after Brexit. Its role is expected to examine new green policies, investigate complaints and take enforcement action against public authorities for breaching environmental law. But will the watchdog have the same bite as the commission?
“A critical question is what level of power the regulator would have in the UK and what relationship, if any, it will have with the EU?” said Jonathan Easton?, planning and environmental barrister at Kings Chambers.
Easton believes that should the OEP try to align its decision-making processes in line with the EU, divergence over the longer term would be minimised. But if it does not, “you will see two different regulatory bodies applying two different systems of environmental protections”. This, he says, could create a system where not only does the UK diverge from the EU, but the devolved nations inside the union diverge too.
Under both scenarios, Easton predicts a plethora of legal challenges on the horizon. “I could foresee a rich seam of legal challenges over the next five to 10 years where the English and Welsh legal system adjusts to life after Brexit.”