EASTERN REDWING 129 



Mabel Osgood Wright (1907) writes: "When Redwings live in 

 colonies it is often difficult to estimate the exact relationship between 

 the members, though it is apparent that the sober brown, striped 

 females outnumber the males; but in places where the birds are un- 

 common and only one or two male birds can be found, it is easily 

 seen that the household of the male consists of from three to five 

 nests each presided over by a watchful female, and when danger 

 arises this feathered Mormon shows equal anxiety for each nest, and 

 circles screaming about the general location." 



Numerous banding records have indicated the males far out- 

 number the females, but this is probably due to the fact that 

 the males enter the traps more readily than the more retiring females, 

 and so are more often recorded. What is probably a more reliable 

 conclusion as to the actual sex ratio was found in the careful studies 

 of J. Fred Williams (1940). He states in his summary: 



In a study of nestling Eastern Red- Wings made at Indian Lake, Ohio, from June 

 18 to July 22 it was found that the young could be sexed by dissection at any time 

 after hatching. 



With the age of nestlings known to the nearest day it proved possible to dis- 

 tinguish between the sexes by means of weights after the fifth day, and by 

 means of tarsal lengths after the eighth day. 



The following sex ratios were found: 



Among 119 young, representing the full egg complements of 35 nests, 57 males: 

 62 females. 



Among 94 young which were successfully fledged, 47 males: 47 females. 



Among 21 young which died during the nesting period, 9 males: 12 females. 



The apparent deviation of the first and third of these ratios from the expected 

 50:50 could easily be due to random variation in sampling. 



To assume that the even 50 : 50 birth rate, or nearly that, is the rule, 

 does not agree with the well-known fact that the females outnumber 

 the males on the breeding grounds, unless we also assume that the 

 females begin to breed when less than one year old and that the males, 

 at least most of them, do not mate until they are nearly 2 years old. 

 This is true of the yellow-headed blackbird, and probably also of the 

 redwing. With the sexes as unbalanced, as they are in the breeding 

 colonies, polygamy is likely to be quite prevalent and promiscuity, 

 or even polyandry, may often occur, through the latter is probably 

 rare. 



Dr. Charles W. Townsend (1920) gives the following excellent 

 account of the courtship display of the male: 



The courtship of the Red-winged Blackbird centers as distinctly about the 

 display of the scarlet epaulettes as does the courtship of the Peacock about the 

 display of his train. The adult male Red-wing when absorbed in feeding is a 

 plain blackbird with a pale yellow stripe on his shoulder or one with a narrow 

 band of red. The color may even be entirely covered up by the prevailing 

 blackness of his costume. When, however, his love passions are excited he spreads 



