IO PLUMAGE OF WARBLERS 



First Fall Plumage. — Leaving aside for the moment the question 

 of the relation of the fall plumage of the young to that of the adult, 

 it will be found that most of our Warblers in first fall plumage 

 conform to the general laws of color in relation to sex and age. These 

 may be stated as follows: 



1. When the adults are alike or nearly alike in plumage, the 

 young in first fall plumage resemble their parents in spring plumage. 

 Examples are Protonotaria, Helmitheros, Helinaia, Helminthophila 

 pinus, H. luciw, Dendroica dominica, the Seiuri, Oporomis formosa, 

 Icteria virens, Setophaga picta, Cardellina. 



2. When the adults in breeding plumage differ, the young of 

 both sexes resemble either the breeding female or the adults in the 

 fall. This class includes by far the largest number of Warblers. 

 Examples are Mniotilta, Helminthophila rubricapilla, H. celata, H. 

 peregrina, Peucedramus, Compsothlypis, Dendroica tigrina, D. astiva, 

 D. coronata, D. auduboni, D. maculosa, D. pensylvanica, D. striata, 

 D. castanea, D. blackburnice, D. nigrescens, D. virens, D. townsendi, 

 D. pdlmarum, D. discolor, Oporomis agilis, 0. Philadelphia, 0. 

 tolmiei. Exceptions are Helminthophila chrysoptera, Dendroica 

 ccerulescens, and Wilsonia mitrata. 



Adult plumage. — Essentially adult plumage, as we have seen, is 

 acquired not later than the first spring molt by all our Warblers except 

 Helminthophila bachmani, Peucedramus, Dendroica chrysoparia, 

 and Setophaga ruticilla, in which it is doubtless acquired immediately 

 after the first breeding season, or in the following spring. 



Once acquired, the adult plumage, as far as color is concerned, 

 may remain virtually unaltered, or it may be changed for a widely 

 different fall plumage to be worn until the approach of the next nest- 

 ing season, when the mature breeding dress is regained. 



These facts may be expressed in two laws as follows: 



i. When the sexes are alike, or nearly alike, in color, the fall 

 plumage of both is generally like the spring plumage. Examples are 

 Protonotaria, Helinaia, Helmitheros, Helminthophila lucioe, H. 

 Virginia, H. pinus, Dendroica dominica, D. gracice, D. kirtlandi, the 

 Seiuri, Chamcethlypis, Setophaga picta, and Cardellina. 



2. When the male in spring plumage differs from the female, he 

 generally resembles her in fall plumage. There are numerous excep- 

 tions to this law but it holds good for most species in which there is 

 marked sexual difference. Examples are: Dendroica tigrina, D. coro- 

 nata, D. auduboni, D. maculosa, D. pensylvanica, D. castanea, D. 

 striata, D. blackburnia. Exceptions are: Helminthophila bachmani, 



