Peter Boggis has won the first round of his battle to stop his home from falling into the sea in a legal action that could become the battle of fossils versus birds.

At the heart of the case is a move by Natural England to designate about seven miles (12km) of Suffolk coastline a Site of Special Scientific Interest (SSSI).

The government agency is charged with protecting more than 4,000 SSSIs in England, covering 7 per cent of the land and its best wildlife and geological sites.

The purpose of the sites is to “conserve or preserve” flora, fauna or geological features – so people living on or owning them have to obtain permission from the agency before they can undertake building work or other activities that might damage the environment.

Natural England found itself in court yesterday, however, accused of wanting to preserve a section of the Suffolk cliffs – only to allow their erosion by the sea.

The story begins with the struggle of a man in his seventies to save his house, which stands close to the eroding shoreline where he has lived all his life, and to take action to shore up that coastline.

Legally, though, it turns on whether Natural England had powers to designate this area a geologicial SSSI in 2006 – and secondly, if it did, whether it went about that process properly.

The agency had argued that the erosion of the seven miles of the Easton Bavents cliffs near Southwold should be allowed to take its natural course, exposing a rich seam of fossils dating from the Ice Age, 1.8 million years ago.

Mr Boggis’s sea defences, it argues, compromise the scientific value of the site by impeding access to the cliff face and encouraging the growth of vegetation.

So they notified Mr Boggis and others affected, saying that erection, maintenance and repair of sea defences or coast protection works required its consent: failure to comply would constitute a criminal offence.

Yesterday Mr Justice Blair ruled that the agency did have power to designate the area an SSSI – even though it planned to allow the erosion of the cliffs.

But the designation was unlawful, he said, because the agency’s notification had amounted to a “plan or project” – which meant that it should have carried out an “appropriate assessment” of the risk to the special protection area of birds, including the rare bittern, to the north of Mr Boggis’s sea defences.

Natural England plans to appeal. But the agency emphasised that the ruling was about the legality of steps taken – not whether Mr Boggis had the right to build sea defences or not.

Mr Boggis, it added, could still seek legal permissions from the district council and the Environment Agency to build sea defences — and it would “encourage” him to go down that route. With that permssion, he would not need Natural England’s consent. Helen Phillips, the chief executive of Natural England, said: “Designation does not make it in any way inevitable that Mr Boggis will lose his home and we have no desire to make this happen.”

If the agency wants to halt Mr Boggis, it must now look at the impact of its plans on the birds – and it looks as if it will have the final word over the future of the fossils.

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