FLUCTUATIONS IN A RED GROUSE POPULATION 

 Table V. Losses of young birds in the first month after trapping 



A. — ist-winter cocks — 

 1956: 



Total tabbed . 



Number disappeared 



Percentage disappeared 

 1957: 



Total tabbed . 



Number disappeared 



Percentage disappeared 

 1958: 



Total tabbed . 



Number disappeared 



Percentage disappeared 



1959: 

 Total tabbed . 

 Number disappeared 

 Percentage disappeared 



B. — ist-winter hens — 

 1956: 



Total tabbed . 



Number disappeared 



Percentage disappeared 

 1957: 



Total tabbed . 



Number disappeared 



Percentage disappeared 

 1958: 



Total tabbed . 



Number disappeared 



Percentage disappeared 



1959: 

 Total tabbed . 

 Number disappeared 

 Percentage disappeared 



Table VI. Changes in numbers of tabbed grouse and casualties recorded 



107 



Numbers of tabbed grouse on the study area 

 Total during autumn . 

 Total recorded 31st December 

 Total recorded ist April 

 Total disappeared during winter 

 Number found dead during winter 



1956-7 



no 



70 



56 



54 



9 



1957 



205 

 93 

 68 



137 

 14 



'-8 1958-9 1959-60 



166 



82 



41 



125 



13 



47 

 23 



(3) HNDING DEAD BIRDS 



We look for dead grouse during counts and they are reported to us by 

 keepers and shepherds who patrol the ground. Much of the area is a lambing 

 moor and is walked several times daily by shepherds in the spring when we 

 also examine the moor thoroughly while searching for nests. It is at this 



