138 Bird Lore 



flood and able to visit afterwards. Of course, many thousands of nests were 

 destroyed in the valley at this time. I found sixteen Red-winged Blackbirds' 

 eggs in one pile of drift, none of which could have come from the nests listed, 

 as they were a mile or more upstream. 



In the case of nests listed as destroyed by boys, it might be well to say that 

 the boys were either caught in the act, or fresh tracks and marks of climbing 

 in the trees were noted which were considered good evidence. Few nests are 

 included whose location was not known before, and as the territory was covered 

 every day, such evidence was usually fairly fresh. On June 24, 1914, when 

 five nests were listed as destroyed by boys, a band of four boys were trailed 

 through a little strip of timber and caught in the act of robbing the last nest. 

 The other eggs were in their possession. 



The following summary of the data shows the distribution of the factors 

 involved in the destruction of these 50 nests: 



Through human agency: 



Nests robbed or destroyed by boys 12 



Destroyed by mowing-machine 7 



Destroyed by cultivator 1 



Destroyed by farmer, purposely 1 



Nest deserted by parents after human interference 1 



Nest destroyed by cutting of stump on which located 1 



Nest destroyed accidentally by boy brushing against it 1 



Total through human agency 24 



By cats and other natural enemies: 



Young eaten by cats 3 



Eggs eaten by Blue Jays 3 



Eggs eaten by snake 1 



Nests destroyed by Starlings 3 



Eggs eaten by fox squirrel 1 



Nest destroyed by English Sparrow 1 



Total by natural enemies 12 



By storm and flood: 



Destroyed by wind and rain 2 



Destroyed by flood n 



Total by elements 13 



Accidental destruction by bird itself 1 



TOTAL 50 



It would obviously be absurd to attempt to draw from so little data any 

 definite conclusions regarding the part played by various agents of destruction. 

 Search of literature and correspondence would doubtless reveal a mass of data 

 from which fairly definite conclusions could be drawn and such work is a 

 possibility of the future. 



