290 U. S. NATIONAL MUSEUM BULLETIN 211 



Economic status. — From the above study of its food habits it 

 appears that the rusty blackbird is of no great economic importance, 

 either one way or the other. It does no great damage to agriculture, 

 for the small amounts of cultivated fruits and berries eaten are 

 insignificant; and, although it consumes considerable grain, this is 

 mostly taken as waste grain during the late fall and winter, and does 

 not interfere with harvesting; some newly sown grain may be picked 

 up in the early spring. On the other hand, as it does not spend the 

 summer in agricultural regions, it cannot be as helpful to the farmer 

 in destroying harmful insects as some other species. But it does 

 enough good to be worthy of protection. 



Behavior. — Mr. Skinner (1928) writes: 



Rusty Blackbirds on the ground walk, and run nimbly, with a nodding of their 

 heads forward and backward in time to their own steps. As compared with 

 other blackbirds, this species is perhaps tamer and certainly more quiet, composed 

 and dignified. When hunting across the ground, members of the flock are con- 

 tinually walking and running, and frequently individual birds fly a few feet to a 

 position at the front. While Rusty Blackbirds fly in dense compact flocks all 

 winter, and appear to enjoy the society of other members of their own kind, they 

 are less apt to join other species. When in flocks composed of several species, 

 the Rusty Blackbirds usually split off into separate flocks composed of their own 

 kind. But at times they vary this and join flocks of Meadowlarks and Starlings; 

 but on the other hand Starlings, Cowbirds and Red-winged Blackbirds more 

 often join the Rusty Blackbirds. During the winter these Blackbirds are also 

 seen temporarily with Bluebirds, Juncos, Doves and Horned Larks. 



While the flocks of Rusty Blackbirds are more dense and compact than most 

 other species, they are not so much so as those of Red-winged Blackbirds. A 

 flock in flight moves steadily onward, but the individual birds undulate up and 

 down, or swing from side to side, so that the relative positions constantly change 

 and give the flock a rippling appearance. They fly either against the wind or 

 with it. In the latter case, just before alighting on ground or trees they wheel 

 and come up to their perches against the wind. In its minor points, the flight 

 of these birds is thrush-like. Rusty Blackbirds are quiet during the winter, 

 but the song also suggests a thrush rather than a blackbird. 



Behavior in Ohio during migrations is thus described by Trautman 

 (1940): "During migrations the birds were found most frequently 

 on wet ground or near water. Many spent the days in the cattail 

 marshes and on the shores of the lake, where they fed while wading 

 in the shallows. In the inland brushy swamps the}'' also fed in shallow 

 water or on wet ground. There were flocks about the 'sky ponds' 

 and overflow puddles in fields, especially in early spring, and small 

 groups were along the banks of the streams. At night all except a 

 few roosted in cattail swamps about the lake, on Cranberry Island, or 

 in the denser and more brushy inland swamps. Throughout the 

 bird's entire sojourn it was a close associate of the Eastern Redwing, 

 and to a lesser extent of the Bronzed Grackle, Cowbird, and Starling." 



