The traditional pheasant hunt in Europe is one where they use drivers to push the birds into a line of waiting guns. Today they use pretty much pen raised birds and toss them into the air and fly over the crest of a hill to be shot by waiting guns. Pretty much a sport of the wealthy now.
This is a quote by the photo
"~ The head keeper at Warton Priory, standing in front of a good day's bag of English pheasant, December 1910. ~"
European shooting is different. You don't have bag limits. But neither do you get to keep the birds. They are picked up and sold by the landowner to local markets. The landowners consider them a crop and are perfectly willing to have you pay them money to help with the harvest.
It appears none of the individuals in the picture are actually the shooters. I see no guns. With their walking sticks and a dog I think these were the drivers and picker uppers. It looks like it is of the gamekeeper and the local help.
The picture is not that outdated. The clothing would change, but in England or on the Continent, after a big shoot, you'd pretty much see the same thing today. In Germany and eastern Europe they always lay out the birds for photos and for a moment of respect for the game.