344 BULLETIN 197, UNITED STATES NATIONAL MUSEUM 



William Brewster ( 1938) , writing of birds at Lake Umbagog, Maine, 

 says : "The males sing regularly until late August, and on September 

 26, 1899, one sang feebly and brokenly," and A. C. Bent says in liis 

 notes that he heard a bird singing daily from August 31 to September 

 14, 1900, in Massachusetts. 



Albert R. Brand (1938) gives the approximate mean vibration fre- 

 quency of the song as 3,600, rather higher than that of the white-eyed 

 and yellow-throated vireos. 



The common complaint note may be written queee^ a discontented, 

 petulant call, inflected downward, about as long as the catbird's snarl. 



Field marhs. — If an observer is near enough to a redeye to see the 

 vireo bill, the gray crown, bordered by black lines, the black line 

 through the eye, the white underparts, and the unmarked wing, it is an 

 easy bird to identify. The red iris, seen only at very short range, is 

 not a reliable field mark. 



The red-eyed vireo in plumage is remarkably like a Tennessee 

 warbler, but the needlelike bill of the warbler and its paler side of the 

 head distinguish the two birds. 



Enemies. — In addition to the the danger of capture by small hawks, 

 the red-eyed vireo is subject to attack by the red squirrel, and the 

 chipmunk, as the two following quotations show, respectively. Wil- 

 liam Brewster (1936) relates this observation made at Concord, Mass., 

 on June 10, 1906 : 



Again this afternoon Gilbert heard the Vireos crying anxiously. Looking out 

 through the screen door, he saw the Squirrel on the branch within a few inches 

 of the nest, eating something. Presently he dropped a portion of the shell of 

 one of the Vireo's eggs. He then wiped his face with his fore-paws and wiped 

 the latter on the branch. The next minutes he bent forward until his head and 

 fore shoulders disappeared in the nest and almost immediately reappeared on 

 the branch with another egg in his mouth. The Vireos assailed him frantically 

 and one of them struck him with her bill when he was in the nest. Probably 

 because of their attacks, he almost immediately took the second egg off with him, 

 running up the main trunk of the tree until lost to sight in the foliage of its crown. 



A. A. Wood (1920) records a similar experience, saying: "Last 

 spring (June 8, 1918) I noticed a Red-eye excited over something, then 

 saw a chipmunk climbing the sapling the bird was in. Wlien he was 

 about eight feet up, the vireo darted down knocking him to the ground. 

 The other bird was on the nest at the end of one of the branches." 



In reference to the cowbird's relation bo the red-eyed vireo, Herbert 

 Friedmann (1929) says : "This bird is so frequently imposed upon that 

 it is difficult to think of the Cowbird getting along without the pensile, 

 cup-like nests of the Red-eye. No species suffers more and few as much. 

 * * * Occasionally this Vireo covers over, or buries (under a new 

 nest floor), the parasitic eggs as does the Yellow Warbler, but on the 

 other hand it has been known to incubate Cowbirds' eggs even when 

 none of its own were present, and almost always seems not to mind 



