YELLOW-BELLIED SAPSUCKER 129 



Nesting. — ^William Brewster (1876a), writing of the nesting of 

 the sapsucker at Umbagog Lake, Maine, says : 



They arrive from the South, where they spend the winter, from the middle 

 to the last of April, and, pairing being soon effected, commence at once the 

 excavation of their nests. The trees usually selected are large dead birches, 

 and a decided preference is manifested for the vicinity of water, though some 

 nests occur on high ground in the interior of the woods, but never so abundantly 

 there as along the margin of rivers and lakes. Both sexes work alternately, 

 relieving each other at frequent intervals, the bird not employed usually 

 clinging near the hole and encouraging its toiling mate by an occasional 

 low cry. With the deepening of the hole arises the necessity for increased 

 labor, as the rapidly accumulating debris must be removed, and the bird 

 now appears at frequent intervals at the entrance, and, dropping its mouth- 

 ful of chips, returns to its work. A week or more is occupied in the com- 

 pletion of the nest, the time varying considerably with the relative hardness 

 of the wood. A small quantity of the finer chips are left at the bottom to 

 serve as a bed for the eggs. * * * The labor of incubation, like all other 

 duties, is shared equally by the two sexes. * * * 



All nests examined upon this occasion [an occasion when he found half a 

 dozen nests] were of uniform gourd-like shape, with the sides very smoothly 

 and evenly chiselled. They averaged about fourteen inches in depth by 

 five in diameter at the widest point, while the diameter of the exterior hole 

 varied from 1.25 to 1.60 inches. So small, indeed, was this entrance in pro- 

 portion to the size of the bird, that in many cases they were obliged to 

 struggle violently for several seconds in either going out or in. The nests in 

 most instances were very easily discovered, as the bird was almost always 

 in the immediate vicinity, and if the tree was approached would fly to the 

 hole and utter a few low calls, which would bring out its sitting mate, when 

 both would pass to and from the spot, emitting notes of anxiety and alarm. 

 The bird not employed in incubation has also a peculiar habit of clinging to 

 the trunk just below the hole, in a perfectly motionless and strikingly pensive 

 attitude, apparently looking in, though from the conformation of the interior 

 it would be impossible for it to see its mate or eggs. In this position it will 

 remain without moving for many minutes at a time, 



Henry Mousley (1916) states that the bird "often nests year after 

 year in the same tree (but not necessarily in the same hole) the 

 favourite ones here [Hatley, Quebec] being elm, poplar, and butter- 

 nut. * * * Qf ^^Q i;iests examined the average dimensions are 

 as follows, viz. : entrance hole 1% inches in diameter, extreme depth 

 10% inches, and width 2% inches." 



Philipp and Bowdish (1917) say of the nesting site in New 

 Brunswick: "The favorite situation was the dead heart of a live 

 poplar, most often on the bank of a stream, and facing same, but 

 some nests were in totally dead trees, of different kinds. They 

 ranged from eight to forty feet from ground." 



Ben dire (1895) says that the birds "are devoted parents, and when 

 incubation is somewhat advanced, or the young have been recently 

 hatched, the bird oil) the nest is loath to have it, and will sometimes 

 allow itself to be captured rather than to desert its treasures." 



