iSo2.] LooMiS on Birds of Chester County, South Carolina. '? I 



steadily in s.trength, the middle of the month and the third week 

 showing- marked increase in many 'resident' and winter birds, as 

 Wilson's Snipe, Vesper and Field Sparrows, Cardinal, etc. The 

 hosts of Rollins and Blackbirds also arrive, and females become 

 more numerous in species represented in winter chiefly by males 

 In forward seasons straggling Grasshopper Sparrows make their 

 appearance. B}- the end of the month the flood tide of the Robin 

 migration is reached. Other birds have been continually 

 strengthened, and a few, as the Bluebird, have waned. The 

 dates given are the approximate average, an open or backward 

 season manifesting corresponding earlier or later ones. The 

 fluctuations in abundance of winter birds, which arise from the 

 passage of successive waves northward, begin to be apparent in 

 this month. At this time of the year the cold is rarely ever of 

 sufl^cient duration to cause pronounced movements from the 

 north. A few Prairie Horned Larks, however, respond to the 

 severer w\aves, and the advancing migrants are sometimes forced 

 back, the scale of local abundance ascending somewhat as in a 

 forward movement. A descent of temperature usually produces 

 but little ert'ect upon the birds that have come up from the region 

 below, though protracted inclemency retards further advance. 



During the first half of March the migration is chiefly a con- 

 tinuation of the movements of February. The. birds that winter 

 mainly below receive further accessions. Other winter residents 

 decline, or exhibit variations in abundance as the waves roll 

 northward, a considerable hiatus often existing between the dif- 

 ferent advances of a species. Cold sometimes checks the migra- 

 tion as in February, holding it in abeyance, but rarely, if ever, 

 brins:in<r about slight regurgitating: movements. 



Middle of March to the Middle of June. — With the coming 

 of the Black-and-white Warbler, about the 15th of Marcii or dur- 

 ing the week following, begins the regular migration of birds 

 that are never found in this locality in the winter. But a few 

 days behind this Warbler arrive the first Blue-gray Gnatcatchers. 

 Both usually become very numerous during the last portion of 

 the month. Bachman's Sparrow, the Yellow-throated Warbler, 

 Maryland Yellowthroat, White-eyed Vireo, Henslow's Sparrow, 

 Bartramian Sandpiper, Parula Warbler, Yellow-throated Vireo, 

 and Black-throated Green Warbler also make their appearance at 

 the end of the month, about as in the order named. The last 



