^"'■^■^n KoPMAN, Bird Mis:ration in the Lozver Miss. Vallev- Ak 



BIRD MIGRATION PHENOMENA IN THE EXTREME 

 LOWER MISSISSIPPI VALLEY. 



BY HENRY H. KOPMAN. 



It can be imagined easily enough that to take up all the con- 

 siderations suggested in the title set to this article would be 

 beyond the possibilities of a single paper for ' The Auk.' My 

 intention is simply to pick out from among the general phenom- 

 ena of southern Louisiana and southern . Mississippi bird migra- 

 tion those important facts to which the general attention of the 

 ornithological world has never been drawn. Aside from the 

 ornithologists of the Department of Agriculture, to which several 

 observers in this section have reported regularly every spring and 

 fall for the past ten years, scarcely any of our ornithologists are 

 acquainted with the striking peculiarities detected in bird migra- 

 tion in this latitude. One of the prominent tendencies, noted by 

 me in a former brief communication to ' The Auk ' (Vol. XX, 

 July, 1903, pp. 309, 310), is procrastination in spring migration. 

 A corresponding tendency is seemingly premature arrival in the 

 fall. Under the first head, a very striking case is that of the 

 three transient thrushes of this latitude, the Wilson's, the Gray- 

 cheeked, and the Olive-backed. The case of these birds comes 

 very readily to mind because it was only the past spring that I 

 settled an important phase of their migrations through Lower 

 Louisiana. Every spring for the past ten years, and not infre 

 quently in the fall, I have been puzzled by a querulous whistle, to 

 be heard, with few if any exceptions, in heavy night migrations 

 the latter part of April and the early part of May, and again the 

 latter part of September. As my knowledge of the conditions of 

 migration have grown I have attributed this note to several spe- 

 cies, each time discovering the impossibility of the suspected 

 bird being the author, until I hit upon the Yellow-breasted Chat 

 as the chief actor in the heavy migrations of the late spring and 

 of the middle fall. In this belief I rested with fair security, so 

 like the mellow whoort of the Chat was the oft repeated note of 

 the night migrations. My first record of this note was the night 

 of April 25, 1894. Heavy rains and an electric storm early in 



