26 BULLETIN 2 03, UNITED STATES NATIONAL MUSEUM 



from the farther shore of a river or pond we were completely deceived. On 

 more than one occasion, when a good opportunity for comparison was offered 

 by the actual presence of both birds at the same time, we found that at the 

 distance of several hundred yards their notes were absolutely undistinguishable ; 

 nearer at hand, however, the resemblance is lost, and a ringing, penetrating qual- 

 ity becomes apparent in the Warbler's song. It now sounds like peet, tsivcet, 

 tsweet, tstveet, or sometimes tivcef, tr-sweet, tr-siveet, tr-siveet. When the bird 

 sings within a few yards the sound is almost startling in its intensity, and the list- 

 ener feels inclined to stop his ears. The male is a fitful singer, and is quite as apt 

 to be heard in the hot noontide or on cloudy days, when other birds are silent, 

 as during the cool morning and evening hours. The ordinary note of alarm 

 or distress is a shari? one, so nearly like that of the Large-billed Water Thrush 

 (Siurus motacilla) that the slight difference can only be detected by a critical 

 ear. When the sexes meet a soft tcliip of recognition common to nearly all the 

 Warblers is used. In addition to the song above described the male has a 

 dilferent and far sweeter one, which is reserved for select occasions, — an out- 

 pouring of the bird's most tender feelings, intended for the ears of his mate 

 alone, like the rare evening warble of the Oven-Bird (Siurus auricapillus) . It 

 is apparently uttered only while on the wing. 



Although so low and feeble as to be inaudible many rods away, it is very sweet, 

 resembling somewhat the song of the Canary, given in an undertone, with trills 

 or "water-notes" interspersed. The flight during its delivery is very different 

 from that at all other times. The bird progresses slowly, with a trembling, 

 fluttering motion, its head raised and tail expanded. This song was heard most 

 frequently after incubation had begun. 



Dr. Koberts (1936) refers to this flight song, as delivered "after the 

 manner of the Maryland Yellow-throat, * * * consisting first of 

 the usual rapid monotone of five or six notes and ending with a pleas- 

 ing, varied warble, full and strong in some of its notes and far sweeter 

 than the usual utterance." 



Dr. Walkinshaw (1938) says of the usual song: "Uttered at the rate 

 of five or six times per minute, the song lasts slightly over one second. 

 It is given all day long from the time of arrival until the young have 

 left the nest and has been heard as late as the 16th of August (1931). 

 The frequency is much greater during the early nesting season and 

 during the earlier hours. During midday on warmer days the number 

 of times per hour seems much less. Later, from four until near sun- 

 down, it again increases. During late nesting, when the young are 

 about to leave the nest, the rate again decreases, but it is heard 

 several days after the young leave the nest." Aretas A. Saunders tells 

 me that the songs are pitched at C'' or B"', and the call note, tseek, 

 at A'". 



Field marks. — The golden swamp warbler could hardly be mistaken 

 for anything else. The rich, brilliant yellow of the head and breast, 

 sometimes almost orange on the head, only slightly paler in the female, 

 the absence of wing bars, and the large amount of white in the tail 

 will distinguish it. 



