BANK SWALLOW 407 



in the course of 7 days; this was also the deepest burrow noted by 

 Stoner. 



Leonard K. Beyer (1938) writes as follows concerning his obser- 

 vations of burrow excavating at a colony near Milton, Pa. : 



Both birds of a pair took part in the work. A bird would begin by cling- 

 ing to the vertical face of the bank with feet and tail and pecking at the dirt 

 with a side-to-side motion of the head. When the opening was deep enough 

 for it to get partly inside it would use its feet also, kicking the loosened sand 

 backward in vigorous little spurts. As the tunnel became deeper the bird 

 disappeared from sight, but still the sand came spurting out as evidence of 

 the work of the little miner inside. 



Bank swallows seem to take the work of excavating their burrows very 

 lightly, more like play than work. Indeed, an eager holiday spirit seems to 

 pervade the flock. A swallow will work vigorously for a few minutes, the 

 while many of its comrades are circling about over the bank talking to each 

 other in their reedy, buzzing twitter. Soon it can no longer resist the tempta- 

 tion and it flies out for a ride through the air with them. But usually not 

 for long, and after a few minutes it returns to its job. These activities con- 

 tinue throughout the day, though at intervals the entire flock may leave the 

 bank for a time. As evening comes on they fly away to some favorite roost- 

 ing place in a nearby marsh. 



The birds begin carrying in nesting materials as soon as the bur- 

 rows are completed. At first the larger and longer grass stalks 

 comprising the foundations of the nest are transported, and later 

 come finer materials to which may be added a few feathers for the 

 lining of the structure. Generally large numbers of feathers are not 

 added until after the set of eggs is completed and incubation under 

 way. According to Stoner the nest is prepared by the combined 

 efforts of the male and female. The birds obtain much of the nest- 

 ing material while they are on the wing, but frequently they may be 

 seen on the ground near the nesting colony picking up dried weed 

 and grass stalks. 



The following description is based on a bank swallow's nest in 

 a large colony located in a gravel pit 5 miles northwest of Topsham, 

 Maine. The entrance to the burrow was V/2 inches high and 2^ 

 inches wide and was 39 inches deep. The extreme outer extent of 

 the nesting materials included an area roughly 6V2 by 5% inches, 

 but the diameter of the central depression occupied by the incubating 

 bird was only 2 inches in diameter and about half an inch deep. 

 The nest itself was a very flimsy structure and would scarcely hold 

 together without the support of the underlying sand. The bulk of 

 the materials was made up of dry grass stems ranging from a half 

 inch to four inches in length. Interwoven with the grass stems were 

 rootlets, white pine needles, two match sticks, and several tufts of 

 sheep's wool. In the interior of the nesting bowl were four well- 

 worn scraggly feathers and small parts of others. This nest, con- 



