The Glorious 12th will begin on the 13th this year - and the grouse season is expected to be as mixed as the date.

Experts are predicting varying fortunes for shooters on the moors of Scotland, which has 75% of the grouse land in Britain, when the season begins on Monday.

People from all over the world will arrive to take part in the shoots. The Scottish Countryside Alliance has asked all those going out to the moors to take out insurance beforehand.

"You wouldn't drive without insurance, so don't shoot without insurance," said a spokesman.

Recent heavy rain means Grampian and the Highlands are expected to see lower-than-average grouse numbers but areas of the Borders and the west of Scotland are expected to fare well.

A survey by the Games Conservancy Trust (GCT), which advises farmers and landowners on improving wildlife habitat, has revealed the numbers of grouse in areas such as Deeside and Donside on the higher ground have been disappointing, probably due to long cold spells in June and persistent heavy rain and snow.

However, high numbers are expected to be shot in the south of the country, which is expected to enjoy a busy grouse season when it kicks off on August 13th, as the Glorious 12th falls on a Sunday.

"In spite of tropical style rain in the southern uplands, the grouse have been determined to breed, with counts up on past years.

"The keepered upper parts of the Tweed catchment and the Lowther Hills appear set for a bumper season with high densities of well-grown broods," said Hugo Straker, the GCT adviser.

He added: "In the Moorfoot Hills, predictions are not as good as 2006 but better than expected. Early broods seem to have succumbed to a cold spell, although there is a strong showing of late broods.

Speaking at the official launch of the season in Scotland's Angus Glens, trust director Ian McCall said: "It was a very mild winter and we had a fantastic spring, which meant the heather came away on the moors early.

"This is important because it means the hen will lay more eggs and a lot of the gamekeepers have been very pleased with the number of chicks they saw."

Mr McCall said he was encouraged by the fact that the number of ticks, which carry Lyme's disease which can affect the grouse, had been reduced.

He said: "In the Angus Glens, it's refreshing to report first signs that tick numbers are declining on those properties which are fully implementing our tick reduction prescriptions.

"The four-year Angus Glens Moorland Health Project, of which we are part, advocates regularly treating all sheep with tick-killing compounds before going to the hill and in effect mopping up' and destroying the ticks.

"Ticks carry and transmit a number of diseases which affect not just grouse, sheep and cattle, but humans too."