JFor Ceacl)ers^ anti Students 



The Migration of Warblers 



FIRST PAPER 



Compiled by Professor W. W. Cooke, Chiefly from Data 

 in the Biological Survey 



With lirawinss by LouiS Agassiz Fuertes and Bruce Horsfall 



EDITORIAL NOTE 



THE series of papers of which this is the first will, we believe, prove 

 one of the most helpful to field students of bird migration which 

 has ever appeared in a periodical. Migrants in the truest sense of 

 the word, most of our Warblers winter in the tropics, and many of them 

 breed in the Canadian zone. Twice a 3'ear, therefore, in surprising num- 

 bers, they sweep by us journeying northward in the spring, after the 

 weather is comparatively settled, and with, consequently, remarkable regu- 

 larity; and returning on their "due dates" in the fall in even greater abun- 

 dance. In short, without the Warblers a study of bird migration in the 

 field would lose half its charm. 



It is well known that for many years the Biological Survey in Washing- 

 ton, under the direction of Dr. C. Hart Merriam, has been gathering data 

 in relation to bird migration. Professor Cooke's ' Bird Migration in the 

 Mississippi Valley ' is based on data obtained in this manner, and is Bul- 

 letin No. 2 of the Survey. A second Bulletin by Professor Cooke on the 

 routes of migration pursued by Warblers will be issued by the Survey 

 during the coming year. In the meantime Professor Cooke has kindly 

 prepared for Bird -Lore synopses of the migration dates of all the North 

 American species of this family; and, in view of what has just been said, 

 it will be readily understood how much more detailed and valuable this 

 material will be than anything on the subject which has heretofore been 

 published. 



Of the Redstart, for example, Professor Cooke writes: ''I believe that 

 the enclosed notes on the Redstart include the largest number of records 

 ever accumulated for one species on this continent. The figures given 

 represent 395 records selected from about as many more." With these 

 records for comparison, it is needless to say that one's own observations 

 will become doubly interesting and significant. 



In concluding the publication of these papers, we shall print a full list 

 of all the observers whose work is cited, with their stations, enabling one 

 readily to ascertain the authority for given dates. — -F. M. C. 



(188) 



