2/8 AMERICAN ORNITHOLOGY. 



' MOULTING. 



By Dr. Morris Gibbs. 



All birds moult, and presumably twice a year, the moult with which 

 we are familiar, the one in the late summer and early autumn, which is 

 more pronounced, often gives a bird a new coat of a different hue. 

 Then the bird changes back to the original spring coat in color; but 

 this latter moult is so gradual that we are hardly aware of the transition. 

 The Bobolink change to an ochraceous in the summer, and then leaves 

 us for the south, but when he returns in the spring he has resumed his 

 coat of black and white, so to speak. The Goldfinch, like the Bobolink 

 changes to the less pronounced colors of the female, yet he stays with 

 us all the year and resumes the sulphur yellow sometimes between 

 October and April."' Yet though I have taken the Goldfinch in the 

 months of January, February and March I have been unable to find 

 that this bird has a complete, that is, sudden change in the early spring 

 like that of the fall. I mention these two species because they are to' 

 an extent alike in adopting the colors of the female, yet are entirely un- 

 like in their winter habits. 



The Bobolink is the first to moult in the Great Lake Region. The 

 moult of this one-brooded species begins by the middle of July, and 

 earlier, and in the last of the month flocks of ten to an hundred may be 

 seen in the meadows a id marshes, when all gradations of plumage may 

 be seen, from the spotted black and white to the perfect fall coat. The 

 complete moult takes considerable time, and throughout the operation 

 the birds continue to fiock and keep low, never rising much above the 

 fence and weeds. The males and females are indistinguishable 

 as they rise and whirl to a little distance. The once dashing songster 

 no longer rises on fluttering wing to stimulate us with his ecstatic, 

 rollicking song. Soon the augmenting flocks leave for the south; and 

 down on the coast they are called reed birds, and later rice birds. 



The Goldfinch nests last, habitually, and it also moults last, for it 

 rarely drops its spring coat until well into October, and I have seen a 

 male in the bright sulphur coat in the very last of the month. A friend 

 of mine took a set of Goldfinch's eggs in September, and certainly this 

 species does not moult until the duties of nesting are through with. 

 The period of moulting depends on conditions affecting both sexes, and 

 these conditions largely depend on the nesting. 



In a large majority of cases the moult takes place within a month 

 after the nesting duties are completed, but this is not a rule as will be 

 shown. It follows that the Hawks and Owls as early nesters, are among 

 the early ones to moult. This is so, and out of over one hundred 



