Weather Conditions in Relation to Grouse 



From the instant a potential grouse comes into existence as a fer- 

 tilized egg to the time it meets its usually violent end, it faces the 

 continuous vicissitudes of the weather. In its incubation period the 

 primary hazard is that of excessive chilling; w^hen a chick, hazards 

 from the heat or cold, the wind, and rain all play a part; while in 

 adult life the bleak cold, snow, ice, and storminess of winter must 

 be faced as they come. Humans, who also face essentially the same 

 handicaps, fare well or poorly in proportion to the adequacy of our 

 shelter and our food supply. To a considerable extent this is true 

 also with the grouse. The better their food and shelter, the better 

 may they cope with the dangers that adverse weather brings. In 

 actuality, since food and shelter are seldom perfect, the weather 

 plays an important part in limiting or reducing grouse numbers, or 

 in preparing the way for destruction by predators. 



EFFECTS OF W^EATHER ON THE HABITS AND 

 NUMBERS OF GROUSE 



Sunshine Gauges the Time of Nesting. The laying of eggs by a 

 hen grouse comes about only after a considerable period of internal 

 physiological change. The dormant ovaries are stimulated to growth 

 in early spring by the lengthening hours of daylight. Once started 

 the development of these organs and the laying of fertile eggs (fol- 

 lowing mating) comes about systematically. However, the date of 

 the beginning of egg-laying varies considerably in different years. 

 To illustrate: On Connecticut Hill the average first egg in 1931 was 

 laid on April 18; in the succeeding year it did not appear until 

 April 27. 



Correlating the variations in nesting dates with the weather factors 

 brings out clearly that sunshine is the guiding element. When we 



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