Migration of the white-throated sparrow 



The white-throated sparrow, 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 Pennsyl- 

 vania, and Massachusetts. The winter range extends from the south- 

 ern 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 November 

 14, 1949, being nearly 283,500. It would be expected that these would 

 yield a comparable number of return records that 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 wintering grounds. Operators of 

 stations in the winter area, as Thomasville, Ga., and Summerville, 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, prob- 

 ably 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 comon. It has been reported 

 as already present by May 25 at the mouth of the Liard River, in south- 

 western Mackenzie. This coincides with the time that first arrivals 

 are noted fully 700 miles north, at Point Barrow, Alaska. The problem 

 has been to ascertain the route used by these birds to their principal 

 nesting grounds in the interior. 



For a long time it was believed that this big diver did not winter 

 in large numbers anywhere on the Pacific coast, and it had been sup- 

 posed that the spring route extended 2,000 miles northeastward from a 

 wintering ground somewhere in eastern Asia to Bering Strait, then 

 500 miles still northeast to round Point Barrow, then 500 miles east to 



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