BARN SWALLOW 443 



Although the above observations were made many years ago, I 

 liave no doubt that in many remote or thinly settled localities barn 

 swallows still continue to nest under similar natural conditions. 

 James B. Dixon writes to me that in San Diego County, Calif., as 

 late as 1925, he found them nesting in caves in the ocean wall. 



Barn swallows were quick to take advantage of the superior nest- 

 ing sites offered by various man-made structures ; and probably they 

 also felt a sense of added security in their close association with 

 friendly human beings. As civilization advanced, the swallows grad- 

 ually learned to adopt such suitable nesting sites as they could find 

 in, on, or under various types of buildings, in or on the outside of 

 barns, sheds, or other farm buildings, inside of vacant houses, under 

 the eaves of dwelling houses, under wharves and boat houses, and 

 under bridges and culverts. In the rural districts of old New Eng- 

 land, the old-fashioned barn, with its wide-open doors and its lofty 

 haymow, seems to be the commonest and most characteristic nesting 

 place. Here their mud nests may be plastered on the vertical sur- 

 face of a beam or rafter, if it is not too smooth, but preferably where 

 it can get some support on the flat surface of a beam or shelf, in 

 the angle of a cross brace, or in a corner where two sides will be sup- 

 ported ; the iron rail of a hay track, a loop of hanging rope, an iron 

 hook, or wire loop, or even a projecting knot on a rough timber may 

 offer the necessary initial support. We seldom find more than six 

 or eight nests in a barn, but I have known of as may as 27 in a single 

 barn here in eastern Massachusetts; and Dr. Charles W. Townsend 

 (1920b) "counted fifty-five nests of this bird in a large barn at 

 Ipswich, nearly all of which were occupied." 



A. Dawes DuBois has sent me some notes on nests under bridges 

 in Illinois. Five of these nests were attached to the vertical face of 

 a floor joist, over water. Another was placed on top of a cross beam 

 at the end of the bridge, fitted into a corner formed by the vertical 

 faces of a joist and another beam at right angles to it. The tops 

 of the nests were about 2 inches below the floor boards of the bridge. 

 A nest under an iron bridge was stuck to the vertical web of an 

 I-beam, but was so placed that the bottom of the nest rested on the 

 lower flange of the beam. 



Frank L. Farley tells me that, near Camrose, Alberta, "the barn 

 swallow has apparently departed entirely from its natural nesting 

 situations. Here they have not taken to the barns, but now they 

 are increasing in numbers and nest entirely under bridges and cul- 

 verts." James B. Dixon says in his notes that in San Diego County, 

 Calif., they nest on the highway bridges that cross the estuaries 

 along the ocean front; and in the San Joaquin Valley he hns noted 

 large colonies under bridges and beet-loading platforms. 



