EASTERN HOUSE WREN 137 



Wasps, bumblebees, fields mice, red squirrels, and chipmunks have 

 also been cited as troublesome to nestling house wrens. 



Friedmann (1938) has reported two cases in which the house wren 

 has been host to the eggs of the parasitic cowbird. The character of the 

 usual nesting site of the house wren is such that they are seldom 

 imposed upon by these molothrine visitors. 



Sometimes man unwittingly becomes an enemy of the house wren 

 by spraying vegetation to kill insect larvae that are eaten by the 

 wrens. Hoffman (1925) writes as follows: "For three successive 

 years the House Wrens have abandoned their nests in the writer's 

 yard when their young were partly grown. The dried remains of 

 the nestlings were found when the nest boxes received a cleaning 

 in the fall. At the time that the nests were abandoned the currant 

 bushes had become infested with the small green currant worms 

 and had been dusted with finely powdered arsenate of lead. It was 

 shortly after the old birds were observed carrying the arsenate- 

 covered worms to their nests that they disappeared and were not seen 

 again." 



Philp (1937) reports that house wrens among other birds were 

 blackened by smudge made during a cold wave to protect fruit from 

 a threatening frost. The carbolic acid in the crude-oil vapor that 

 covered both their food supply and their plumage was not enough 

 to prove fatal to the birds, but Philp states the birds were so saturated 

 with the greasy oily deposit that they could not regain their normal 

 colors until the following molt. 



During migration fatalities frequently befall the house wren when 

 it flies into lighthouses and tall city buildings. Overing (1938) re- 

 ports that a house wren was killed by flying against the Washington 

 Monument, thus sharing the fate of many other species of birds. 

 Sometimes wrens are carried out to sea by storms: Sprunt (1931) 

 states that a house wren came aboard a ship when it was well out 

 to sea off Cape Lookout, N. C. It crept under the winches and 

 about the mooring bilts for the better part of an hour. 



Fall. — In September the house wren, as we know it as a tenant 

 in our nesting boxes during summer, undergoes a marked change 

 in behavior, in song, and in plumage. At this time it deserts the 

 environment of man and resorts to the deep recesses of the woodlands, 

 where it skulks among the tangled underbrush making its presence 

 more difficult to detect. The song as previously noted may con- 

 tinue, but it undergoes considerable modification. Its plumage is 

 grayer and darker than the garb worn in summer. Little wonder 

 that Audubon thought the bird he observed at this season to be a 

 different and a distinct species, which he described as the wood wren. 



In New England and in most of its summer range the last house 

 wrens remain until the middle of October, but the majority of them 



