Table 1. — Weights of willow ptarmigan from several parts 



of Alaska 





Males 



Females 



Date 



No. 



Weight (g.) 



No. 



Weight (g.) 





Extremes 



Averages 



Extremes 



Averages 



Anaktuvuk Pass 

 November-December 1948 

 April 1949 



February-March 1950 

 March 1952 



4 



1 



7 



13 



504-627 



706 



461-804 



580-743 



506-730 



450-617 

 473-519 



600 



601 

 633 



(621) 

 615 



(619) 

 530 



539 

 (535) 



2 



4 



7 



20 



500-625 

 504-627 

 430-704 

 527-706 



495-749 



446-525 

 493-627 



563 

 560 

 544 

 617 



Arctic Village 

 December 1951-February 1952 



25 

 14 



33 



15 



(591) 

 641 



Arctic 

 Chugach Momitains 



December 1951-February 1952 

 Talkeetna Mountains 

 December 1950, January 1951, and Feb- 

 ruary 1951 



39 

 12 



3 



48 

 8 



5 



(607) 

 495 



573 



Subarctic 



15 



13 



(525) 



In the winters of 1948, 1949, 1950, and 1952 the mean of the weights 

 of 128 arctic ptarmigan was 619 grams. Among willow ptarmigan 

 taken in winter in the Chugach and Talkeetna Mountains about 600 

 miles south from Anaktuvuk the mean weights of 28 birds were 531 

 grams. In Mount McKinley National Park, Alaska, Dixon (1927) 

 reported the average weight of male willow ptarmigan (of this race) 

 in the breeding season to be 507 grams. My records (11 males from 

 Anaktuvuk during April and May weighed 538 grams.) indicate that 

 arctic willow ptarmigan are lighter in summer than in winter. While 

 he was on the eastern arctic coast of Alaska in winter Anderson ( 1921) 

 reported that 15 willow ptarmigan weighed 22 pounds which gives an 

 average weight of 652 grams. 



The distribution of weight about average in arctic willow ptarmigan 

 is shown in the following tabulation : 



Number 



Sex 



Percentage distribution about average 

 weight 



±10% 



39 Male 

 49 Female 



54 

 52 



96 

 89 



100 

 100 



The difference between the winter ptarmigan of arctic and subarctic 

 Alaska points to the arctic ptarmigan being significantly heavier than 

 those from the subarctic locality. On the basis of weight differences 

 of similar proportions (about 1 kg. in 5 kg.) von Zedlitz (1924) 



