EASTERN YELLOW WARBLER 173 



"Singing continues from the first arrival in migration until the 

 third week of July, ceases for a short time, but is usually revived in 

 August, and is to be heard irregularly until the birds depart for the 

 south." 



Francis H. Allen gives me his impressions of the two common songs 

 as follows: "One of these I have been accustomed to render as wee 

 see icee see wiss iviss'-u. Occasionally the final wiss'-u is doubled. The 

 other of these two songs goes something like wee wee wee witita weet^ 

 without the drop in the pitch that the first song has at the final note. 

 I have also heard a song of five single notes with no variation in pitch 

 or tempo — weet weet weet weet weet. Besides a rather sharp cJiip^ 

 which is the ordinary call-note, I have heard a dzee from a yellow 

 warbler." 



The yellow warbler is an early riser. Mr. Smith (1943) heard one 

 begin singing at 4 : 56 a. m., "daylight time," and another at 4 : 05, 

 "but with only one song until 4 : 08 when seven were given during 

 the space of one minute. During the song period of fifty minutes, 

 197 songs were given." Dr. Charles W. Townsend told Mr. Allen 

 that he heard one at Ipswich, Mass., on June 13, 1908, that began sing- 

 ing at 3 : 10 a. m., but this was standard time. 



Dr. Winsor M. Tyler (1937) mentions a peculiar note, heard during 

 the migration in August, which had puzzled him for nearly 30 years 

 until he finally traced it to an eastern yellow warbler. "As we walk 

 under the trees, listening, we hear a long, wild, high, sharp bird-note, 

 abrupt, and very slightly vibratory, lasting perhaps half a second. 

 It is a characteristic sound of this time of year, and we hear it best 

 on these quiet, silent days. It comes from a bird moving restlessly up 

 in the trees, and before we can see the bird, it is gone. * * * jj^ 

 pitch, it suggests the call of a migrating Ovenbird, but it is too long- 

 drawn-out; it suggests the chip of a Northern Water-Thrush in its 

 sharp abruptness, but again it is too long." 



According to Albert E. Brand (1938) there is considerable varia- 

 tion in the pitch of the song of the eastern yellow warbler, from 8,775 

 vibrations per second in the highest note to 3,475 in the lowest note, 

 and with an approximate mean of 5,900 vibrations per second. This 

 is far below the approximate mean of 8,900 for the black-poll warbler, 

 but well above the average of 4,000 for all passerine birds. 



Field marks. — One hardly needs field marks to recognize a yellow 

 warbler; it is the yellowest of all our warblers at all seasons, even 

 the wing and tail feathers are edged with yellow, and there is no 

 white in either wings or tail. The youngest birds likewise show some 

 yellow on the under parts and in the flight feathers. See the descrip- 

 tions of plumages for details. 



