400 U. S. NATIONAL MUSEUM BULLETIN 211 



framework." William Youngworth (1932) reports a similar situa- 

 tion as follows: "In July 1929, I watched several pairs of bronzed 

 grackles attending to nesting duties at Scranton in southwestern 

 North Dakota. The birds had built their nests on the steel beams 

 inside of a large coal briquet plant which was not in operation at the 

 time." In correspondence, Lyle Miller writes that a large colony of 

 grackles nest on the girders of a large water tower at Youngstown, 

 Ohio, and he has also found numbers nesting on the girders of a large 

 steel bridge at Lake Milton, Ohio. Others have reported finding 

 them in similar situations, sometimes in places shared by nesting 

 phoebes. A most unusual nesting site is in the bulky masses of the 

 osprey's nests. Apparently the grackles are not molested by the 

 giant birds, and from the associations have derived protection as well 

 as scraps from the osprey's dinner table. 



The nesting season ranges from the first week of March to the latter 

 part of June, depending on the latitude and various conditions of the 

 locality. In the extreme southern sections of the range, nests are com- 

 mon early in March. The height of the nesting season in Massachu- 

 setts is reached about the middle of May; but in Maine, and also in 

 the more northern sections of the range, most of the nests are built 

 in the latter part of May and in June. 



The structure of the nest of the bronzed grackle varies much less 

 than do the nesting sites. It is always a substantially built, bulky 

 affair of sticks, coarse grass, weeds, roots, leaves, and similar materials. 

 In most nests a liberal supply of mud in the interior serves to plaster 

 the loose nesting materials into a more permanent mass. Inside the 

 mud layer is a lining of fine grasses and rootlets ; sometimes hair and 

 feathers are added. Many of the nests I have seen in the corn belt 

 of the Midwest had foundations made up almost entirely of corn husks. 

 Some of the nests, especially those near human habitations, had the 

 foundation materials interwoven with string, paper, and rags. The 

 nests are deeply cupped and serve well to hold the active young that 

 are to follow. A typical nest has an outside diameter of 7 inches and 

 a depth of 5 inches; the nesting cavity is 4 inches in diameter a,nd 3% 

 inches deep. 



The nests of the grackles are usually so well made that many of 

 them remain in good condition even after being exposed to the buffet- 

 ing of winter storms. H. Elliott McClure (1945) found many such 

 nests, eight of which were used by mourning doves. 



Eggs. — The eggs of the Florida, purple, and bronzed grackles are 

 similar, and the reader is referred to Bendire's (1895) description 

 under the account of the purple grackle. According to Bendire: 

 "The average measurement of a series of one hundred and forty-eight 

 specimens in the United States National Museum collection is 29.02 



