WESTERN HOUSE WREN 145 



ished. Soon after the young in the first nest were hatched, and 

 although needing much attention, the old birds still frequented the 

 new nest, and I began to suspect that one of them was sitting on eggs 

 there. This suspicion was soon verified by hearing the young, and 

 seeing them fed. In this case each parent must have been sitting at 

 the same time on a nest, perhaps taking turns, during the week that 

 elapsed before the first hatching." 



Young wrens are known to return to their nest to roost at night 

 for a while after leaving the nest. Miss Merritt (1916) tells of a 

 brood of four young wrens that, on the second evening after leaving 

 the nest, were escorted by their mother to an empty catbird's nest in 

 a syringa bush, where they spent the night. "The entire family of 

 four young ones returned with the mother each evening for 14 days. 

 On the fifteenth evening one of the young wrens was missing ; on the 

 next evening two did not return." On the evening of the seventeenth 

 day the one remaining young refused to remain in the nest; it flew 

 away and never returned. The mother bird never roosted in the cat- 

 bird's nest, and her roost was not discovered. 



Food. — The food of the western house wren agrees so closely in its 

 general character with that of the eastern bird, that what has been 

 reported on the food of the latter will illustrate very well the food of 

 the former. Prof. Beal (1907) examined only 36 stomachs from Cali- 

 fornia, of which he says that "animal matter, consisting entirely of 

 insects and spiders, formed 97.5 percent, and vegetable food 2.5 per- 

 cent. Beetles, as a whole, amount to about 20 percent; caterpillars, 

 aggi-egating 24 percent, are taken in the earlier months of the year ; 

 and Hemiptera, amounting to 33 percent, are eaten chiefly in the 

 last of the season. Grasshoppers amount to about 5 percent, and dif- 

 ferent insects, mostly ants and other Hymenoptera, aggregate 15 per- 

 cent." 



The western bird is evidently just as beneficial in its food habits as 

 its eastern relative. About the only useful insects that it destroys 

 are the coccinellid beetles, or ladybugs, and it destroys no fruit. 



I cannot find any evidence that it has the harmful habit of destroy- 

 ing the nests or eggs of other birds, of which the eastern bird has been 

 so often accused. It is seldom imposed upon by the western races of 

 the cowbird; Dr. Friedmann (1938) records only two such cases; the 

 entrance to its nest is generally too small for the cowbird to enter. 



Fred Mallery Packard sends me the following note from Estes 

 Park, Colo.: "House wrens arrive in the park early in May, to be- 

 come the most abundant songster of the pines and aspens through the 

 Transition and Lower Canadian Zones. They sing during the nesting 

 season, which starts early in June ; and some sing to the end of July, 

 when most of the young of the second brood are fledged. They ap- 

 pear to depart early — late in August and early in September— -but 

 there is one October record." 



