The owners of exclusive seafront homes have been ordered to tear up parts of their gardens to make way for a nature reserve.

Many of the detached houses in Old Fort Road, Shoreham, encroach on to a narrow strip of derelict land between their gardens and the beach - a designated conservation site.

Arun District Council wants to reclaim the wasteland to extend the nature reserve and sent letters to homeowners asking them to remove paving and walls by the end of October.

The residents are complaining they are being treated unfairly because four householders have been allowed to buy parts of the land and keep their plots whereas others, who took over the wasteland more recently, have been told there is nothing they can do.

The homes, which are valued at up to £800,000 overlook a stretch of shingle which is home to some of the rarest sea plants in the world. One species is only found in Japan and New Zealand.

Parts of the beach have been declared a site of nature conservation interest (SNCI) and there are plans to create a nature reserve on other sections.

The strip of wasteland contains the remains of ugly Twenties sea defences which have crumbled or been partly demolished.

It also contains the rusting remnants of the old Norfolk suspension bridge which once spanned the nearby River Adur.

Resident Richard Davies said moving in diggers would damage the habitat of the common lizard, which is protected under the Wildlife and Countryside Act 1981.

He said: "It is much better to fence off the areas concerned to allow our rare and precious lizards to get on with their lives undisturbed. To humans the environment which has been there for at least 39 years may not be attractive but to our lizards it is heaven.

"It would be ironic if the cack-handed use of diggers to establish the reserve resulted in the extinction of the creatures it was set up to protect."

Another resident, accountant Peter Jarman, 46, said: "Three houses to the right of us have all extended their gardens and built brick walls around them and have since bought the land.

"There are two rules: One for the people who have just taken the land and another for those who have asked for permission to get the land and not got it. That seems to be unfair."

But management consultant, John Ross, 55, welcomed the council's move. He said: "If you lived next to Buckingham Park, it would not be acceptable to extend your property by stealing bits of the park."

The removal exercise will affect 83 homes. The council will bring a digger in to remove the old sea defences as they are thought to be a safety hazard.

When Anthony Brown, 30, bought his house, it came with an extended garden built by the previous owners with planning permission from the council.

He said: "People have to do things the right way. If there are no boundaries, people will steal beach until there is none left."

Jeremy Crook, head of legal and democratic services, wrote to residents urging them to respect the council's ownership of the land.