Efforts to protect one of Britain's most endangered birds, the black grouse, are proving a major success in three North-East valleys, a survey shows.

Their numbers have grown in recent years in Teesdale, Weardale and South Tyne-dale, although they have declined in other places.

By 1998, there were only 789 males left in England, but that rose to 893 by 2002, with 80 per cent of them in the three North Pennine dales.

Another count being organised this spring is expected to show that the numbers have risen again, to at least 1,000, thanks to the efforts of the Game Conservancy Trust.

The trust set up a black grouse recovery project in 1996 in partnership with several other bodies, including English Nature and the RSPB, and this has stemmed a decline which had gone on for years.

Females are expected to reach the same number, although they are more difficult to count as they are more secretive in the breeding season.

Phil Warren, the project officer based at Forest-in-Teesdale, said yesterday the success had been achieved by reducing sheep grazing on moorland fringe habitats and showing landowners and farmers how to help the species.

Grants have also been given to assist this work.

Black grouse numbers declined because of poor rearing habitats, attacks on nests by stoats and weasels, and repeated poor weather in June, when the chicks hatch.

Three quarters of Britain's black grouse are reared in Scotland, but the totals there have continued to fall, while the North-East decline has been reversed.

The species used to breed all over Britain and was shot in large numbers. Despite the decline, it is still legal to shoot the birds, but there is a voluntary ban in place.

Mr Warren added: "We are hopeful that, if funding is given for another five years of the project, the black grouse will start to breed in other parts of Britain."

He will start the task of counting the male black grouse in Teesdale in April, and this will continue in May in the rest of the region.