A FOREIGN invader is heading for East Anglian coasts and cannot be stopped, experts have warned.The invader is an alien species of seaweed, called Japweed, which threatens native vegetation and the marine ecosystem, according to English Nature, the Government's wildlife watchdog.

A FOREIGN invader is heading for East Anglian coasts and cannot be stopped, experts have warned.

The invader is an alien species of seaweed, called Japweed, which threatens native vegetation and the marine ecosystem, according to English Nature, the Government's wildlife watchdog.

Reports that it has already colonised parts of Suffolk, have yet to be confirmed.

Ian Reach, maritime protected areas officer for English nature, said the weed, which looks like a shiny brown fox tail floating in the water, had now colonised the whole of the south coast and the west coast as far at Strangford Lough in Northern Island.

It had already been confirmed in north Kent and it was "inevitable" that it would reach East Anglia.

Mr Reach said the weed, which grows on rocks and concrete harbour walls and jetties, was thought to have been introduced to the UK through French imports of oysters from the Pacific region.

"It drifted across the English Channel and is now threatening to choke British estuaries, rock pools and marinas," he said.

Experts are worried that the invader could wipe out native kelp "forests" which are the marine equivalent of the tree forests of temperate climes and part of the native eco-system.

"It spreads through fragments becoming detached and carried to other areas by boats or the movement of currents.

"The most likely way for fragments to be broken off is through watersports or storms," Mr Reach said.

The low-lying sand and mud shores of Suffolk would escape the weed but it would attach itself to harbours and marinas. In Norfolk it would colonise rock pool areas.

Japweed was first detected in the UK along the coast of the Isle of Wight in 1971 and has spread since then at the rate of about 20 miles a year.