THE MIGRATION OF NORTH AMERICAN BIRDS bo 
the mountains of Haiti in the middle of May when others of the 
species are en route through North Carolina’ to breeding territory 
in New England or have even reached that region. Redstarts 
(Setophaga ruticilla) and yellow warblers (D. aestiva), evidently the 
more southern breeders in each case, are seen returning southward 
on the northern coast of South America just about the time that 
the earliest of those 
breeding in the North 
reach Florida on their 
way to winter quar- 
ters. 
NOCTURNAL AND DIUR- 
NAL MIGRATION 
When one recalls 
that most birds ap- 
pear to be more or less 
helpless in the dark, 
it seems remarkable 
that many should 
select the night hours 
for extended travel. 
Among those that do, 
however, are the great 
hosts of shore birds, 
rails, flycatchers, ori- 
oles, most of the great 
family of sparrows, 
the warblers (fig. 4), 
vireos, and thrushes, 
and, in fact, the ma- 
jority of small birds. 
Thatit is common to 
find woods and fields 
on one day almost 
barren of bird life and 
on the following day 
filled with sparrows, 
weap vers, “and 
thrushes, would indi- 
eate the arrival of - - 
migrants during the oo ee a Paste 
night. The passage B2282M 
of flocks of ducks and  Ficurr 4.—The Kentucky warbler, a night migrant, in traveling to 
- : f 1 7 its winter quarters in Central America and northwestern South 
geesel1s requent yWAOD= America, uses route no. 5, figure 20. 
served by sportsmen 
sitting in their blinds, but great numbers of these birds also pass 
through at night, the clarion call of the Canada goose (Branta cana- 
densis) or the conversational gabbling of a flock of ducks being 
common night sounds in spring and fall in many parts of the country. 
The sibilant, nocturnal calls of the upland plover, or Bartramian 
sandpiper (Bartramia longicauda), and other shore birds during their 
spring and fall flights form vivid memories in the minds of many 
