402 U.S. NATIONAL MUSEUM BULLETIN 237 part i 



Acanthis hornemanni exilipes. All were lined with ptarmigan feathers 

 and some with caribou hair as well. 



In 1953 Baldwin and Reed examined 25 nests of the hoary redpoll 

 near Umiat on the Colville River about 75 miles south of the Arctic 

 Ocean. Of these nests, 16 were in or under willow, 6 were in alder, 

 1 in an unidentified shrub, and 2 were on artificial substrates at camp. 

 The height at which these nests were placed varied from ground level 

 to 84 inches. 



The female redpoll constructed the nest but was accompanied 

 during her work by the male. The whole nest apparently was built 

 in 3 days, and the lining of fine materials and ptarmigan feathers 

 added in less than 24 hours. The main nesting materials were the 

 coarse grasses Arctigrostis latifolia and Calamagrostis sp., and also 

 cotton from cottongrass and willow. Lesser amounts of alder and 

 wiUow twigs, heath shrub roots, caribou hair, and vole (Microtus) 

 fur were used in some nests. All nests seen were lined with ptarmigan 

 feathers. 



Eggs. — The number of eggs varies from three to six, with four or 

 five most frequently comprising the set. They are ovate or short- 

 ovate, and slightly glossy. The ground may be either "bluish 

 glaucous" or "pale Niagara green," delicately spotted and speckled, 

 with shades of reddish browns such as "warm sepia," "snuff brown," 

 "Mars brown," and a few specks of black, with undermarkings of 

 "light drab," "Ught cinnamon drab," or "pale brownish drab." 

 Some eggs may be marked only with the light undertone spots of 

 "light cinnamon drab," while in others the shades of brown such as 

 "snuff brown" or "Mars brown" predominate. There is, in general, 

 a tendency for the markings to become heavier toward the large 

 end where sometimes a fine, loose wreath may be formed; or again 

 there may be very fine indistinct specklings scattered over the entire 

 egg. 



The measurements of 40 eggs average 16.7 by 12.5 millimeters; 

 the eggs sho^ving the four extremes measure 18.6 by 12.7, 17.8 by 

 13.5, U.O by 11.9, and 17.3 by 10.9 millimeters. 



Cade and Shaller (Kessel, MS.) in 1952 found nests with from one 

 to six eggs between June 12 and July 15. One nest contained one 

 egg, one had two eggs, one had three eggs, four had five eggs, and one 

 had six eggs. Bet\veen June 25 and July 4, they found four additional 

 redpoll nests containing five eggs and young mixed, or just five young. 



Baldwin and Reed in 1953 found the average clutch size to be 

 five eggs in 13 clutches under observation at the time the first egg 

 hatched. However, when seven nests discovered after at least one 

 egg had hatched were considered, the average came down to 4.7 eggs 



