134 THE GROUSE IN HEALTH AND IN DISEASE 



With the hen, however, it is very different, for at this time she leads an even 



quieter life than usual. She feeds constantly, takes no part in the warfare of 



her mate, and becomes to a greater or less extent " broody." When 



Hen in * 



breeding in this condition she does not readily take the wing, and puts on flesh 



season. 



and fat. By the time she begins to lay she has a very large store of 

 surplus fat deposited throughout the body and in masses under the skin ; and 

 from this reserve she draws during the three weeks of incubation. For the 

 twenty - three days during which she " sits " she leaves the nest only for a 

 few minutes night and morning, to eat and drink, and her tracks and 

 "clocker" droppings are to be found always at the springs or drinking-places, 

 which happen to be nearest to her nest. 



At the beginning of the nesting season the hen Grouse weighs as much 

 as a heavy cock, sometimes even up to 27 ounces ; but this holds good for 

 a short time only. It is just during these two months of the year, April 

 and May, that she suffers most from " Grouse Disease " ; an inexplicable fact, 

 did we not know that for various reasons, which are given below, March is 

 to be considered the most dangerous month of the whole year for infection 

 with Strongylosis. 



As the hen sits, her weight, even in health, rapidly diminishes. She is living 

 largely upon her reserve material, and has, in addition to produce from eight 

 to ten eggs. This must be a very considerable drain upon her system, 

 since each egg weighs about an ounce, and each ounce so lost to her is an 

 ounce of her " flesh and blood," the whole amounting sometimes to nearly half 

 her eventual total weight. By the end of June, thanks also to the trials 

 of a family, she reaches an average weight of less than 20 ounces, and by the 

 end of July sometimes falls to 19'5 ounces, whereas the cock, benefiting daily 

 by the improving food and weather, gradually rises from 19 or 20 ounces 

 in March to an average of 24 ounces in August. 1 



It will perhaps throw light on the cause of the marked changes which appear 

 in Tables A and B if an attempt is made to account for them month by month. 



In Table A, for example, which gives the monthly averages for the healthy 

 male Grouse, there is a very decided fall from 24 '2 ounces in February to 

 21'45 in March, with a gradual rise again from April to August. 



This sudden drop must be due to courtship, rather than to shortage of 

 food, for though food is scarce at this time the shortage makes no difference 



1 Vide p. 145, note. 



