HOST RELATIONS OF PARASITIC COWBIRDS 47 



Only in the last case are there any details; the observer left the 

 following account. He found 15 or more doves' nests in one orchard 

 on May 25, and he noticed a cowbird flutter off a large graclde's nest, 

 which, on examination, was found to contain only a single cowbird 

 egg. Three days later, he noted that a mourning dove had deposited 

 2 eggs in this nest. He was unable to visit the nest again until three 

 weeks later, when it contained a young cowbird almost ready to fly. 

 Although he waited for some time, he did not see the doves return to 

 feed the young parasite. 



This account is accompanied by a photograph of the nest, showing 

 the young cowbird and the 2 dove's eggs, but it is not as completely 

 convincing as it might appear to be. Kellogg did not actually see 

 the doves at the nest, and, secondly, the original builders of the nest, 

 the gracldes, might have taken over the nest and hatched and reared 

 the cowbird. Thirdly, it would be theoretically diflBcult for a dove 

 to rear a cowbii'd because of the lack of attunement in their feeding 

 habits. The cowbird chick agrees with nestlings of most other 

 passerine birds in its mode of feeding. At the approach to the nest 

 of the adult food-laden bird, the nestlings open wide theu- bills and 

 the adult thrusts the food with its bill into the throats of the young. 

 The dove, however, reverses the process: the adult opens its mouth, 

 into which the young thrust their bUls for food. It would seem that 

 a young cowbird and an adult mourning dove might have difficulties 

 in adjusting to this difference. This is w^hat raises a question as to 

 the proper interpretation of Kellogg's record. 



A possible sixth record is the following. Watkins (1900, p. 71) 

 writes that cowbird eggs have been found in the nests of several 

 species of birds that nest in open meadows in Michigan, among which 

 he lists the mourning dove. However, in his account of the dove, he 

 mentions only a single instance of ground nesting by this bird in open 

 meadows, and in that one no mention is made of any cowbu'd eggs. 

 It is, therefore, not clear if Watkins knew of a Michigan record, or 

 merely mentioned the mourning dove because of the then fau'ly recent 

 Iowa record published a few years earlier by Coues. Other writers 

 who have listed the mourning dove as a cowbird victim, such as 

 Bendire (1893) and Davie (1889), obviously were merel}^ compiling 

 earlier statements. 



Ground Dove 



Columbigallina passerina (Linnaeus) 



This dove is a rarely victimized species, for which there are only 

 two records, both from near Brownsville, Texas, and both having to 

 do with the dwarf race obscurus of the brown-headed cow^bird. In 

 May, 1925, I examined about a dozen nests of the ground dove, one 

 of which, found on May 23, contained 1 cowbird egg in addition to 



