PRACTICABILITY OF ARTIFICIAL GROUSE PRODUCTION 499 



In terms of chicks (8 weeks old) per laying female, substituting the actual figures for sym- 

 bols, one may obtain the following estimates secured by applying the formulae 



L= Befhl: 



Optimistic L = B x 18 x .80 x .80 x .50 

 L = B X 5.76 

 L = Number of breeding females x 5.76 chicks per female 



Pessimistic L = B x 12 x .65 x .70 x .30 

 L = Bxl.64 

 L = Number of breeding females x 1 .64 chicks per female 



Average L = B x 15. x .725 x .75 x 40 

 L = B X 3.26 

 L = Number of breeding females x 3.26 chicks per female 



In listing items such as production indices and equations, it is difficult to avoid the impli- 

 cation that those who would breed artificially may confidently expect to maintain such a pro- 

 duction schedule year by year. In actuality, it should be remembered that the field is still 

 far too young to justify any such expectation. 



Conversely, by adopting, in general, the methods and techniques previously described and 

 by paying strict attention to the business at hand, it is fair to assume that a skillful breeder, 

 about every other year, may equal or occasionally exceed the estimates of mass production 

 given here. 



It is, of course, understood that considerable time must first be spent in building up a 

 breeding stock properly selected for egg production, fertility, livability of resultant chicks 

 and adaptability to the conditions of captivity. The smaller the number of breeders and 

 chicks, the better the record is likely to be. 



There is one other point not to be overlooked. The number of young grouse reared 

 during the current experiments has varied from a low of less than one bird per hen to a 

 high of 7.5 for the best year's average. The differential is in part traceable to the various 

 experiments carried on, to improvements in the brood stock, the feed and the methods of 

 handling the birds. Year by year, however, it was the individuals responsible for incubating 

 the eggs, rearing the young birds and caring for the breeders on which success, in no small 

 measure, depended. Inexperience, even in one job, was inevitably reflected by a seriously 

 lowered production. As indicated later, exceptionally well trained and competent men deeply 

 interested in the problem are a prime requisite to success. 



Factors Limiting Production 



A difficulty understood is a difficulty half overcome. Thus it becomes particularly pertinent 

 to consider the major known factors that limit the production of large numbers of grouse in 

 captivity. Many of these are biological. Others revolve around the scarcity of breeding 

 stock or eggs, the lack of trained manpower, the cost involved in setting up the necessary 

 plant and the carrying out of the techniques of production. 



Biological Limitations 



Many of the limitations within the birds themselves already have been discussed. 



The inherent capacity of grouse to adapt themselves to the requirements of captivity in 



