EASTERN HOUSE WREN 125 



Baldwin and Bowen (1928) state that out of 104 nests under 

 observation at Gates Mills, Ohio, 86 broods were successful. "The 

 total number of eggs laid by all females under observation was 

 581. Of these 424 or about 73 percent hatched, and 390, or about 

 67 percent left the nest as normal young. The remaining 33 percent 

 perished at one stage or another." 



The instincts of the house wren are so strongly developed in certain 

 individuals that curious situations sometimes occur. Mrs. Bridge 

 (1911) reports a single pair of birds nested on her premises, but 

 two nests were constructed, one in a gourd and the other in a bird- 

 house. When the young were hatched the brood in the birdhouse 

 were fed by the male alone but the young in the gourd were fed 

 by both members of the pair. The inference is that after the female 

 laid both sets of eggs she incubated the eggs in the gourd while the 

 male took care of those in the box. 



Kendeigh (1941) records cases of multiple nesting as follows: 



Although the female ordinarily remains with the young until they become 

 independent, there is a tendency towards the end of the first period when the 

 nestlings are being cared for in the box for the female to begin preparations for 

 a second brood. She may inspect other boxes either of the same male or of other 

 males in different territories. If acceptable, mating may occur very soon, nest- 

 lining inserted, or even egg-laying begun before she is through caring for her 

 first brood. It is but a small step to actual desertion of the first brood by the 

 female in order to start a second brood that much sooner, but desertion does not 

 ordinarily occur without provocation. When the female leaves, the male will 

 ordinarily care for the young alone. He mostly stops singing and applies himself 

 assiduously to the task of hunting food for his offspring. However, he does not 

 brood nor does he stay in the box at night. If the female deserts before the 

 young have acquired self-regulation of their body temperature, death usually 

 follows, but after a week's development, the male is often able to bring them off 

 successfully. 



It has been observed that house wrens that for some reason or other 

 fail to raise a brood of their own and sometimes individuals that do 

 not succeed in obtaining a mate will satisfy the urge for caring for 

 offspring by feeding the adults or young of other species. Hills ( 1924) 

 reports a case in which a house wren fed the adults and young of 

 grosbeaks as well as a family of English sparrows. His account is as 

 follows : "The female Grosbeak was on the nest and a House Wren was 

 bringing small caterpillars to her, which she took from the Wren's 

 beak and fed to her young. At first it seemed to me as though the 

 Wren was liable to be cited as co-respondent, but soon the male Gros- 

 beak came and relieved his mate on the nest, yet the Wren continued 

 to come with food which the male Grosbeak likewise received and fed 

 to the young. * * * Both of the Grosbeaks sometimes themselves 

 ate the Wren's offerings, in place of feeding them to their young. The 

 Wren made more trips to the nest than both Grosbeaks combined." 

 After the young grosbeaks left the nest the wren persisted in feeding 



