Part II.] NATURAL ENEMIES OF BIRDS. 233 



this ■window be protected from climbing animals by sheets of 

 zinc, nailed on the outside of the building. This was done and 

 no more squabs were lost, but gray squirrels were seen to fall to 

 the ground in their attempts to climb or jump into the win- 

 dow. Years passed without absolute proof of chick killing, 

 but recently Mr. O. L. Curtis, assistant manager of the great 

 estate called Seven Gates, formerly the country home of Profes- 

 sor N. S. Shaler at North Tisbury, told me that many chickens 

 on the place were killed, as was supposed, by rats, but not 

 eaten, only the grain being taken from their crops. One of 

 his men saw a gray squirrel in the act. Mr. Curtis then 

 watched, saw a squirrel go into a coop through a hole in the 

 wire, kill a chicken and eat the grain from its crop. He shot 

 the squirrel and several more that came to the coop later. 

 This habit of the gray squirrel probably is exceptional. 



Flying Squirrel {Glaucomys volans volans). 

 Hundreds of nesting boxes for birds that have been put up 

 in trees in Massachusetts have been occupied by squirrels, 

 and while the two preceding species have been the chief tres- 

 passers in most cases, flying squirrels sometimes have outnum- 

 bered the reds, where the nesting boxes have been put up in 

 woods. The flying squirrel moves about mainly at night and 

 little is known about its habits, but I once found one occupy- 

 ing the recently completed nesting hole of a downy woodpecker, 

 and suspected that it had robbed the nest. So far as I know, 

 however, no one has yet convicted the species of nest-robbing. 



Chipmunk {Tamias striatus lysteri). 

 This species is not much complained of as a nest-robber, 

 and although well able to climb trees it is more at home on 

 the ground. It is a meat eater and has been known to rob 

 nests. It is said to swallow young birds. Three observers 

 have reported this, and Mr. W. L. McAtee informs me that re- 

 mains of a young bird were found in the stomach of a chipmunk 

 dissected at the Biological Survey. I have recorded else- 

 where the killing of a wounded bird by a chipmunk.^ As a 



i Special Report on the Decrease of Certain Birds and its Causes, with Suggestions for Bird 

 Protection, fifty-second-annual report, Mass. State Board of Agr., 1904, p. 505. 



