into flocks or "packs," which associations last until the following spring. Their food is 

 largely vegetable, especially buds, shoots, and seed-heads of heather, but those who 

 live where heather is absent must subsist on other food. 



The red grouse is probably the most important game Ijird of the British Isles. Great 

 estates are devoted primarily to grouse moors, and August 12, traditional opening day 

 of the shooting season, has come to be regarded almost as a national holiday. Game- 

 keepers and biologists have made exhaustive studies on how best to conserve the sup- 

 ply. They have seen that neither too few nor too many birds are left over for "seed" 

 and have studied the efTects of disease, cover, weather, and predators on the popula- 

 tion. 



"Driving," as it is called, has become the most popular method for shooting the 

 birds. The gunners take up stations in prepared blinds or huts, and a line of beaters 

 starts toward the gunners, frightening the birds into flight. The grouse are driven past 

 the gunners, usually at full speed, oflTering a wide variety of shots. 



Though only red grouse are shown here, the heathlands in Britain on which these 

 grouse live may support a fairly heavy population of birds. In a study on a moor in 

 Yorkshire, where the vegetation was mainly heather, with some grass and whortle- 

 berry, the breeding bird population on 144 acres was as follows: six twites (a rela- 

 tive of the redpoll), eight reed buntings, six skylarks, sixty-two meadow pipits, four 

 song thrushes, two ring ousels, four wheatears, two winechats, two wrens, two merlins 

 (pigeon hawks), two teals, fifteen golden plovers, eighteen lapwings, three dunlins, 

 and eighty-two red grouse. The average was 15f adult birds to the 100 acres, or a bird 

 and a half to the acre, according to the observer, David Lack. 



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