Lake Maxinkuckee, Physical and Biological Survey 579 



on the 18th ; in September, they were noted on the 18th, 22d, 28th, 

 and 30th; in October, on practically every day, particularly large 

 flocks on the 14th, 25th, and 29th; in November, they were noted 

 on the 2d, 3d, 9th, llth, and 20th. 



In 1901, the first was seen March 3, and they were observed 

 almost daily thereafter up to July 7 when our observations ceased. 



In 1902, the first one was seen March 6, and they were noted 

 again on June 19 and 20, October 19, November 1 and 2, and De- 

 cember 31. 



In 1903, they were common as early as March 5. 



In 1904, they were noted almost daily from October 18 to De- 

 cember 11. 



In 1906, they were observed throughout the summer and up 

 to November 12. 



In 1907, our note books contain entries from September 7 to 

 October 29. 



Our only record for 1909, is February 26, when Mr. Chadwick 

 noted their arrival. 



Our only record for 1911, is November 17, when Mr. Chadwick 

 saw four. 



In 1913, it was noted almost daily during the period of our 

 stay at the lake, September 3 to October 26. 



A pair were seen copulating April 7, 1901. They were ob- 

 served May 29, building a nest in a hole in a fence post on Long 

 Point. On June 2, one egg had been laid, and on June 6, there 

 were five. The old bird was observed on the nest June 14 ; on the 

 18th one egg had hatched ; on the 24th, four lusty young were ob- 

 served and on the 26th they were well developed. 



In this region their favorite nesting places are abandoned wood- 

 pecker holes in old fence posts and old dead snags, particularly in 

 old orchards. 



During the period of clearing the timbered land in Indiana, 

 say from 1850 to 1870, and before the farmers had done much in 

 the way of removing the stumps, every field contained hundreds 

 of stumps one to three feet high, of oak, maple, elm, sycamore, 

 hickory, ash, walnut, tulip, and other hardwood trees. Many of 

 these were hollow, the hole being often only three to six inches in 

 diameter, and these holes were favorite nesting places for blue- 

 birds. The senior author remembers distinctly one large 18-acre 

 field in which stumps were particularly abundant and in which 

 there were many bluebirds' nests every spring. An estimate of 

 five bluebird nests per acre, or 90 for the field, would be a very 

 conservative one. 



