Hen harrier numbers have increased in parts of Scotland

The Royal Society for the Protection of Birds Scotland said the number of pairs rose from 436 in 1998 to 633 in 2004.

But the hen harrier population has fallen in areas where there are grouse moors, situated in the south and east of the country.

RSPB Scotland's Stuart Housden welcomed the hen harrier rise, but said illegal persecution remained a problem.

The hen harrier breeds on moors, bogs and in open forests. It is recognised by its long wings and tail.

We urge responsible moorland managers to work with us to prevent wildlife crime Stuart Housden RSPB Scotland

Mr Housden said: "Hen harriers are graceful birds, which are a favourite with birdwatchers and conservationists.

"Sadly, it seems they are less welcome on the grouse moors of northern England and Scotland, where numbers have fallen and illegal persecution is strongly implicated.

"Hen harriers rightly receive the highest levels of legal protection, and we urge responsible moorland managers to work with us to prevent wildlife crime and find acceptable ways of reducing conflicts between conservation and field sports."

Land management

Professor Des Thompson, of the Scottish Raptor Monitoring Group, said the statistics were encouraging as they meant that most people in Scotland could see the birds.

He said habitat improvements in Orkney and changes in land management in the Hebrides and western Highlands had contributed to the rise in the hen harrier population.

Prof Thompson said action was required to ensure the hen harrier was not lost in parts of mainland Scotland.

The Scottish Gamekeepers' Association said hen harriers should be encouraged to nest in areas where they did not come into conflict with grouse moors.

Group chairman Alex Hogg said: "Worldwide, hen harriers do not have heather moorland in which to nest and we welcome the fact that Scottish Natural Heritage has now realised that and is acting on our advice."