18 



THE BIRD-LIFE OF A YEAR. 



Plate 

 No. 



April SO to SO. 

 11. Spotted Sandpiper. 

 10. Semipalmated Sandpiper.* 



27. Whip-poor-will. 



28. Chimney Swift. 

 Least Flycatcher. 



55. Towhee. 



Blue-headed Vireo. 



Plate 

 No. 



86. Purple Martin. 

 1. Cliff Swallow. 

 1. Bank Swallow. 



Rough-winged Swallow. 



60. Black and White Warbler. 



61. Black-throated Green 



Warbler. 

 67. Brown Thrasher. 



BIRDS NESTING. 



(In addition to the species which began to nest in March, all of 

 which will have eggs or young in April, the following may be 

 found nesting) : 



Plate 

 No. 



April 1 to 15. 



76. Woodcock. 



14. Red-shouldered Hawk. 



20. Screech Owl. 



Red-tailed Hawk. 

 80. American Crow. 



Long-eared Owl. 

 90. Bluebird. 



Plate 

 No. 



April 15 to SO. 



71. White-breasted 



hatch. 

 89. Robin. 

 13. Mourning Dove. 

 37, 91. Purple Grackle. 

 32. Phoebe. 

 41. Song Sparrow. 



Nut- 



MAT. 



As the season advances, marked changes in tem- 

 perature are less likely to occur, and the migration 

 becomes more regular and continuous. In Febru- 

 ary and March there may be two weeks or more 

 variation in the times of arrival of the same species 

 in different years ; in May we can expect to find a 

 given species within a day or two of a certain date. 

 Nevertheless, we shall find the force of the migra- 

 tory current still closely dependent on meteorologic 



* Transient Visitant passing further north. 



