The grouse shooting season got under way a day later than usual this year because the so-called "Glorious Twelfth" fell on a Sunday.
Although the grouse shooting season officially starts on August 12 under the Game Act 1831 England and Wales, it is an offence for any person to kill or take game on a Sunday or Christmas Day.
There are no statutory restrictions in Scotland but it is customary not to shoot game on Sundays.
The British Association for Shooting and Conservation (BASC) said that prospects for the season are mixed due to the recent bad weather.
However, it said the full impact of the wet weather on grouse breeding numbers probably will not be known until after the season starts.
Scottish Land & Estates, which represents more than 2500 landowners in Scotland, praised the grouse shooting industry for bringing tourism, environmental and economic benefits.
It said many of these have an impact all year round.
On Monday Tim Baynes, of the Scottish Land & Estates moorland group, said: "It is clear that grouse shooting brings substantial economic benefits to Scotland - the most recent figures show this to be around £30m a year in monetary terms.
"This comes mainly through tourism and we are delighted that organisations like VisitScotland have now come on board to more robustly support country sports tourism through their website.
"Very many rural businesses depend on grouse shooting for the income it creates and these in turn enable fragile communities to survive through the creation of jobs, both direct and indirect.
"The other important factor is the ecological benefits the moorland management associated with grouse shooting brings.
"This means more diverse wildlife is supported and more carbon is captured, resulting in an improved ecosystem overall."