'"'i'M:t KX ] Bbbotold, A Study of the House Finch. 43 



been •Iik- largely, if no1 entirely, to the enlarged facilities for nesting 



brought, about by the presence <>l' buildings creeled, and trees and 

 vines introduced, through civilization^ and to a larger food supply 

 afforded the birds, resulting from ( he great increase of seed bearing 

 weeds wbicli lias Followed the plowing of the virgin prairies on vvliieb 



the city grew. Furthermore the waste Food products of this city 



form a large source of Food For these birds, and have added to the 



other factors leading to (he increased abundance of this species. 

 It would appear from this that we have here another example of 



man's unconscious aid in the multiplication of an indigenous bird 

 population and fortunately For Denver, this species has probably 

 been largely, iF not wholly, beneficial, thus making For the com- 

 munity's good. 



The House Finch Is resident in Denver, though some facts relat- 

 ing to its seasonal incidence lend color to \\x- idea that it may be 

 locally migratory. During August and September of each year 

 there is a noticeable diminution of Finches about, the city. This 

 is the time when the burdens of nesting and raising oF young are 

 practically over, permitting young and old to flock on the prairies 

 to feed on weed seeds: numerous records of flocks seen in the 

 suburbs about this time, and later, would confirm the above idea. 



It is exceedingly difficult to determine if the same individuals 

 remain in one's neighborhood throughout the entire year. During 

 the summer of L908 an effort was made to throw light on this 

 question. Sixteen young birds, all raised in the writer's nesting 

 boxes, were tagged with a light brass band, the same having been 



placed about the right, tarsus of each bird before if left the nest. 

 With the exception of one, which was found crushed ill the alley 

 the day after it. flew from the nest, none of these Ifi birds was ever 



again identified about the premises. This might, be taken as mean- 

 ing that the young did not remain permanently about the nest 

 neighborhood, but it may be that such tagged birds did remain in 



the neighborhood, but were undetected. 



In the summer of 1909, several young birds were tagged with 

 brass bands on the left tarsus, and in 1910 some with brass bands 

 on both tar ii, with the hope thai such marking would aid in deter- 

 mining how old a Finch might grow to be if left to nature, and all 

 the vicissitudes of bird life. This tagging has shown definitely 



