The Audubon Societies 



307 



they never arrived. Instead the Blackbirds in the South likewise disappeared. 

 The mystery of their disappearance, however, can easily be explained by any- 

 one who will venture out into the heart of the larger marshes^ during the first 

 of September, for there he will find, after sufficient search,* large flocks of 

 short-winged, short-tailed Blackbirds skulking about the more_open areas and 

 hesitating to fly far. For it is at this period that they are just completing their 





W*"'" 



' 



CAPTIVE MALLARD DRAKES 

 The bird at the right is in full plumage which it wears from September to June. The bird at the left is 

 in 'Eclipse' plumage. This corresponds to the winter plumage of other birds, but it is worn only from July 

 to September, during which time the flight feathers are lost and regained. 



molts by the replacement of the outer primaries, the loss of which in short- 

 ening the wing, makes flight difficult and the long flights to the uplands prac- 

 tically impossible. Hence they are seldom seen and it might easily be con- 

 cluded that they had left for other parts. 



Thus it is with other birds also. They cease singing and go into hiding 

 until the molting is practically completed, but it is not long before they regain 

 their former vitality and some even revive their full springtime songs. The 

 majority, however, prefer to rest after their strenuous labors, filling their crops 

 with fruits and seeds and laying up a store of fat that will serve them in the 

 long journeys that they are about to undertake. 



In studying the fall plumage of birds it is always interesting to compare 

 them with their spring plumages and try to determine what changes have taken 

 place through the molt and what further changes will be necessary to bring 

 the birds once more into their breeding plumage. Just as the streaked breasts 

 of young Chipping Sparrows and the spotted breasts of young Robins show 

 their family relationships, so the fall plumages of many birds are indicative of 

 their relationships. Bay-breasted and Blackpoll Warblers, for instance, that 

 are so different in the spring are almost indistinguishable in the fall. Every 

 bird has some interesting phase to its plumage-change and so, no matter how 

 scarce birds may seem, one can always find something interesting to watch or 

 toward which to direct the observations of his students. — A. A. A. 



