LAND BIRDS. 603 



parts. Unlike many of our warblers it is seen during migration in flocks 

 of considerable size, often frequenting open grounds, even stubble fields 

 and pastures, although it prefers bushy fields and the margins of woods. 

 It is one of the earlier warblers to arrive from the south, entering the state 

 as early as April 17, 1886 (Petersburg, Trombley), although ordinarily 

 it is somwehat later, reaching the southern counties about the last week 

 in April and arriving in the Upper Peninsula the first or second week in 

 May (Big Sable Light, Lake Superior, May 9, 1891). There are numerous 

 records of the Yellow-rump killed on Spectacle Reef Light, Lake Huron, 

 from May 7 to May 22, and again from September 25 to October 10. Doubt- 

 less birds reared in the state move southward earlier than this, since migrants 

 appear in the southern part of the state late in August, sometimes even 

 by the middle of the month. It is one of the latest of our warblers to 

 depart, usually remaining through most of October and occasionally into 

 November. Mr. Swales records several seen near Detroit Noveml)er 25, 

 1893. 



In central and northern Indiana Myrtle Warblers are known to winter 

 irregularly in some numbers according to Butler, who says: ''Their 

 winter range does not seem to be limited by the degree of cold, for some 

 of our colder winters, when the thermometer registers below zero, they 

 remain, and warmer winters are not observed. * * * Late in March and 

 early in April they frequent the thickets fringing our streams. * * * 

 They do not really occur outside their winter home until a number of 

 other warblers have arrived in southern Indiana, but every year they 

 occur about the same time and they usually move forward and possess the 

 land at once; two or at most a few days suffice to cover the state" (Birds 

 of Indiana, 1897, p. 1050). 



In their summer home in northern Michigan they seem to prefer the 

 vicinity of evergreens, and are oftenest seen among dwarf spruces, balsams 

 and tamaracks, about the edges of swamps or along the margins of streams 

 and lakes. In such situations they nest, building a rather compact 

 structure of twigs, grasses, etc., lined with finer materials of the same 

 kind, and perhaps a few feathers, the nest being placed in an evergreen 

 often only three or four feet from the ground, although sometimes at an 

 elevation of ten or twelve feet. Max M. Peet gives his experience with 

 this bird on Isle Royale, Lake Superior, in 1905, as follows: "Fairly 

 common in the balsam and spruce forest, but was often found feeding 

 along the rocky shores. A nest containing four well feathered young 

 was found July 7. It was in a Jack pine at the end of a horizontal limb 

 about ten feet from the ground. It was composed of balsam twigs and 

 needles and lined with feathers of the Sharp-tailed Grouse and Canada 

 Jay. July 27, 1905, another nest was found on an island at the north side 

 of Rock Harbor. It was placed on a horizontal limb of a white spruce 

 about six feet from the ground. It was composed of small twigs and 

 grasses, lined with feathers and contained three young about three days 

 old. Four nests were found on two small islands near the end of Rock 

 Harbor, one of which contained small young, another nearly full-fledged 

 young July 21, and the other two were empty. On July 28 a young Myrtle 

 Warbler just out of the nest was found on a small island" (Adams' Rej)., 

 Mich. Geol. Surv., 1908, pp. 374-375). 



The eggs arc four or five, cream-colored or white, with spots of brown 

 and purplish, and ])oihaps a few black specks. They average .70 by .53 

 inches. 



