THE MIGRATION OF NORTH AMERICAN BIRDS 63 
birds unquestionably had made a flight that had every appearance 
of being a true migration to winter quarters in Missouri and Arkansas. 
The black-capped chickadee is apparently resident in many places, 
but occasionally in winter it invades the range of the southern Caro- 
lina chickadee (Penthestes carolinensis) and in northern Canada it is 
regularly a migrant. 
In the coastal plain between Washington, D. C., and the Atlantic 
Ocean, the white-breasted nuthatch is usually absent durmeg the 
summer, nesting at that season in the higher, or piedmont, country. 
Late in fall, however, it appears in fair abundance in the wooded 
ee remaining at the lower levels until the following March 
or April. | 
Some birds, including the screech owl (Otus asio), bobwhite, 
Carolina wren, and mockingbird (Mimus polyglottos), seem to be 
actually sedentary, but even these are sometimes given to post- 
breeding wanderings. Ordinarily bobwhites that are marked with 
numbered bands are seldom retaken far from the area where banded, 
but sometimes they will travel 10 miles or more. A screech owl 
banded at Glenwood, Minn., in March, was recovered the following 
December at Emmetsburg, Iowa, 180 miles south. Such flights, 
however, are probably more in the nature of a search for new feeding 
areas, or to escape from a winged enemy, than a true migratory 
journey. 
MIGRATION OF THE WHITE-THROATED SPARROW 
The white-throated sparrow (Zonotrichia albicollis) (fig. 29), one of 
the most abundant members of its family, breeds from northern 
Mackenzie and the southern part of the Ungava Peninsula south to 
southern Montana, northern Pennsylvania, and Massachusetts. The 
winter range extends from the southern part of the breeding range 
south to the Gulf coast and northeastern Mexico. It is therefore 
a common migrant in many sections. Since it is a ground-feeding 
bird and is readily attracted to the vicinity of dwellings, it has been 
banded in large numbers, the total to February 1, 1935, being nearly 
100,000. It would be expected that these would yield a comparable 
number of return records, and that the facts would furnish basic 
data relative to the migrations of the species. Such, however, is 
not the case. Banded white-throated sparrows are rarely recaptured 
at stations between the breeding and the wintering grounds. Opera- 
tors of stations in the winter area, as Thomasville, Ga., and Summer- 
ville, S. C., have obtained return records showing that these birds 
do come back to the exact winter quarters occupied in previous 
seasons. The fact that they do not again visit banding stations on 
their migration routes indicates some unusual aspects of their travels, 
which it is hoped will eventually be discovered by banding studies. 
Problems of this type constitute definite challenges to the student of 
bird migration. 
MIGRATION OF THE YELLOW-BILLED LOON 
The semiannual movements of the yellow-billed loon present an 
unusual problem in migration. It breeds along the Arctic coast, 
probably from Cape Prince of Wales eastward to Franklin Bay, and 
also in the interior of northern Canada south to Clinton-Colden, 
Aylmer, and Artillery Lakes, where it is rather common. It has been 
reported as already present by May 25 at the mouth of the Liard 
