HOW BIRDS MIGRATE 49 



feed in open, exposed situations, and in their daily excursions for food 

 often cover considerable distances. As a rule they are of bold, restless 

 disposition, and when alarmed or pursued seek safety in long flights 

 rather than by concealment. 



"3. Species which migrate exclusively by day habitually feed 

 either on the wing or over very extensive areas. N In disposition they 

 are either trustful and unsuspecting, or wary and self-reliant. Without 

 exception they are birds of strong, easy flight, and rely solely on their 

 wings for escape from danger." 



A wedge of honking Geese, a close-massed flock of chattering 

 Grackles or Red-wings, a straggling train of Crows or Hawks, are 

 familiar evidences of diurnal migration; while the passage, by day, 

 of the Wild Pigeon was one of the most pronounced and impressive 

 of daylight travels by migrating birds of which we have any record. 



Other of our land-birds " which migrate freely, chiefly or exclusively 

 by day" (Brewster, I. c.) are the Hummingbird, Chimney Swift, Horned 

 Larks, Blue Jay, Waxwing, Shrikes, Swallows, Pipit, Robin and Blue- 

 bird. To this list may be added certain gregarious Finches, like Cross- 

 bills, Siskins, Redpolls, Pine and Evening Grosbeaks, Purple Finches 

 and Snow Buntings. I have also seen Dickcissels, high in the air, 

 traveling in compact bodies by day, though they apparently also 

 migrate by night. 



Ducks, Shore -birds (Limicolse) and Sea-birds (Alcidse, Longi- 

 pennes, and Tubinares) migrate both by day and by night. The sports- 

 man is first made aware of the passage of Plover or Yellow-legs by their 

 mellow calls, as they journey through the air beyond the reach of 

 unaided vision. 



An interesting note on the diurnal migration of birds at an appar- 

 ently high altitude, is supplied by R. A. Bray ('95) who records a 

 flight of birds observed through a telescope, directed toward the sun, 

 at 3 P. M. on September 30, 1894, at Shere, England. Every few seconds 

 a bird was seen to pass slowly across the sun, and there was no decrease 

 in their numbers during the ten minutes of observation. The birds 

 were flying in a southerly direction and were invisible to the naked 

 eye. 



The daily flight of vast numbers of Sea-birds along the Pacific 

 coast is recorded in detail by L. M. Loomis ('06, p. 280) who states 

 that on one occasion (September 23, 1896) "not less than a quarter of 

 a million" Dark-bodied Shearwaters "passed in review during two 

 hours and a half." "There were several divisions each a solid phalanx 

 about an eighth of a mile deep following closely one upon the other," 

 low, over the water. 



Loons may be seen migrating by day, but the weaker winged Grebes, 

 relying on their diving powers for safety, evidently travel by night. 

 Other water-birds, like the Bitterns, Woodcock, Wilson's Snipe, Rails, 

 Coots, and Gallinules, whose habits do not lead them over the sea or 

 its shores, migrate, as Brewster has said, by night. 



