244 BULLETIN 16 2, UNITED STATES NATIONAL MUSEUM 



or in combination with other factors. The evidence points to the 

 conclusion that the vast majority of the parasites and diseases of 

 our game birds have been introduced through poultry and exotic 

 game birds. It is apparent that the adaptation of the prairie chicken 

 to the conditions imposed by civilization is not a simple matter. In 

 this adjustment, birds such as the prairie chicken will require much 

 organized assistance on the part of conservation commissions, 

 sportsmen, and bird lovers. 



Courtship. — The courtship of the prairie chicken generally begins 

 during the first warm days that lay bare the open fields of the 

 winter's accumulation of snow. Though an early beginning may be 

 made, the courtship does not reach its maximum until the latter part 

 of April or the first of May, when companies of prairie chickens 

 majr be seen collected in favorable, often traditional, spots of the 

 open fields throughout the prairie-chicken country. 



O. M. Bryens, of Luce County, Mich., reports the first booming, 

 or " crowing," as it is generally termed in the Middle West, as 

 March 22, 1925; March 13, 1926; April 17, 1928; and March 27, 

 1929. According to Prof. W. W. Cooke, the booming of the prairie 

 chicken was from March 7, at Caddo, Okla., to March 24, at Barton, 

 N. Dak. 



The courtship season continues through the month of May, but 

 the vigor of its execution diminishes and the number of individuals 

 that take part decreases as the sets of eggs hidden in the grasses of 

 the prairie are completed and the domestic duties of incubation on 

 the part of the female begin. 



A few .birds were still booming on the prairies near Hancock, 

 Wis., when I arrived there the first week of June, 1929, and birds 

 were also booming the second week of June, 1930, in various parts 

 of Wood and Waushara Counties, central Wisconsin. I heard no 

 booming and obtained no authentic accounts of birds booming after 

 the second week of June. 



The courtship of the prairie chicken is similar to that described 

 for the heath hen, but since these performances are such an import- 

 ant part of the behavior of this bird a number of interpretations as 

 made by other observers are of great interest. 



Dr. Frank M. Chapman (1908) has given us a very vivid account of 

 the prairie chicken as he observed it in the sandhills of Nebraska : 



At short range the bird's note suggested the mellow resonant tone of a ket- 

 tledrum, and when bird after bird, all still unseen, uttered its truly startling 

 call, the very earth echoed with a continuous roar. As a rule, each bird had 

 itsi own stand separated by about ten yards from that of its neighbor. The boom 

 is apparently a challenge. It is preceded by a little dance in which the bird's 

 feet pat the ground so rapidly as to produce a rolling sound. This cannot 

 be heard for a greater distance than 30 yards. It is immediately followed by 



