1270 U.S. NATIONAL MUSEUM BULLETIN 237 part 3 



The third week in December shows a sharp drop in new arrivals. 

 The graphs now follow a long flat line through late December, January, 

 February, and frequently into March, broken only by dips as a lone 

 bird or two drifts in, and by occasional abrupt peaks during periods of 

 heavy snow or extreme cold. The timing of these peaks is too irregular 

 to indicate anything but local movements of birds in search of food. 

 Most of the birds comprising them disappear as soon as the snow melts, 

 perhaps to reappear during another storm in the same or a subsequent 

 year, suggesting residence in a neighboring territory rather than 

 migration. Meanwhile the traps are visited regularly by a small but 

 constant number of repeaters, the birds that occupy the immediate 

 trapping area throughout the season. 



Field counts corroborate this pattern. Over a 6-year period 73 

 counts were made in a 20-acre tract surrounding the banding station. 

 While the number of Harris' sparrows varied from year to year 

 depending on weather and habitat changes, the proportions from 

 month to month followed this same trend and showed a fairly stable 

 population throughout late December, January, and February. 

 Other groups could be anticipated regularly in favorable spots within 

 a half mile of the station. 



The size of the wintering territory of a Harris' sparrow flock appears 

 to be quite limited under normal conditions. Restricted laterally by 

 the brushy and weedy fringes of a particular hedgerow or timbered 

 ravine, it may extend several hundred yards longitudinally and follow 

 up side branches or tongues of suitable cover for shorter distances. 

 Our regular repeaters remained roughly within the 20 acres adjoining 

 our home, which included three banding traps 300 feet apart, a lawn 

 with various feeding devices, and weedy borders of a garden, chicken 

 yard, and brushy ravine. The birds visited two of the traps inter- 

 changeably and the third trap, nearer the house, less often, usually 

 during severe weather. 



During the winter of 1961-62 Donald D. Bridgwater (MS) operated 

 banding traps at four other territories occupied by wintering flocks 

 from % mile to % mile distant from my home station. Birds at each 

 station were also marked by gluing differently colored chicken feathers 

 to the tails with household cement, and trailed in scores of field cen- 

 suses. Of the 254 banded, approximately half did not repeat at any 

 station. His study revealed that more than half the repeaters 

 banded at my home or the nearest substation, % mile down the brushy 

 ravine, traveled the intervening area fairly freely. Another station 

 only }{ mile away but not linked with the ravine system showed only 

 a 9 percent interchange, whereas a third station % mile distant at a 

 well-landscaped home with a continuous feeding program revealed a 



