WHITE-THROATED SPARROW 1369 



thick bush on rocky ground, 3 feet up in a raspberry bush, and in a 

 brush heap some distance above the ground. Walter B. Barrows 

 (1912) records a nest 3 feet from the ground in a small balsam fir. 

 Harrington (unpubl. notes) found a nest built 10 feet from the ground 

 in a leaning cedar tree. A. F. Ganier and F. W. Buchanan (1953) 

 found a nest 18 inches from the ground in a bog. All 42 of the nests 

 found during the study in Algonquin Park were on the ground. 



Of the nesting habitat in Newfoundland, Peters and Burleigh (1951) 

 write: "They nest in cut-over land, second growth, open woods, 

 brushy thickets and upon hillsides. They choose wet thickets as well 

 as dry ones and may be found anywhere except the thick spruce 

 woods." A similar nesting habitat in eastern United States and 

 Canada was described by Forbush and May (1939) : "Normally this 

 bird breeds in the glades of coniferous woods, preferring northern firs 

 and spruces, but on the hills from which most of the spruce has been 

 cut, it often remains to breed in the waste left by the lumberman." 

 Toward the southern limit of the breeding range in Ontario, white- 

 throats nest in isolated patches of conifers, particularly cedar swamps 

 and spruce bogs (Macoun, 1904). In the prairie provinces white- 

 throats are abundant in the boreal forest to the north, and also occur 

 to the south in the forested valleys of the Saskatchewan River and its 

 tributaries. These valleys are forested with aspens (Populus tremu- 

 loides), balsam poplar (P. balsaminifera) and spruce (Picea spp.) 

 (Houston and Street, 1959). In British Columbia, the species breeds 

 in the parkland deciduous forests in the Peace River and Vanderhoof 

 regions (Munro and Cowan, 1947). The forests in these regions are 

 similar to those along the Saskatchewan River. 



Of the 42 nests Lowther found in Algonquin Park, 36 were built 

 under blueberry, the remaining 6 under mountain rice grass, sweet 

 fern, beaked hazel, or haircap moss. Of the 36 nests built under blue- 

 berry, 28 were under plants 6 to 12 inches high. Two others were 

 under cover less than 6 inches in height, and 13 were under cover 

 greater than 12 inches high. Of the 42 nests 36 were on level ground; 

 of the 6 on sloping ground 2 were placed in the middle of 10-foot 

 embankments. 



Structural canopies were present over 34 of the 42 nests. In all 

 cases the canopy was a natural feature of the nesting cover — 29 nests 

 were each under a mat of dead fronds of bracken fern (Pteridium 

 aquilinum) from the previous year, 4 were under clumps of dried 

 mountain rice grass, and 1 was under the tip of a lower branch of a 

 30-foot white spruce tree. The remaining 8 nests that did not possess 

 a canopy were divided into two groups— those located in cover greater 

 than 12 inches in height, and those built later in the season in cover 

 lacking an overstory of live bracken fern. 



646-737 — 68 — pt. 3 9 



