82 



arrival of migrant adult males, continues for about two weeks 

 before the resident birds begin to arrive. Each evening there 

 is a well-defined flight into the marsh; each night the birds 

 all roost together; and each morning they all leave for the 

 north. The marsh to them at this period is a shelter for the 

 night only, and the entire day is spent on the uplands. Fre- 

 quently there is a lull of a few days when there are no birds 

 migrating, and at this time none will be found in the marsh 

 even at nightfall. The marsh is still flooded, and the vegeta- 

 tion has not yet started (Plate I, fig. 1). 



Arrival of Resident Adult Males. — The arrival of resident 

 males is first made clear by the actions of the birds themselves. 

 To one unfamiliar with their habits the exact time of arrival 

 is not apparent. Up to this time the birds, for the most part, 

 have kept in more or less well-defined flocks. They have 

 been difficult of approach, the slightest annoyance starting 

 them off. The birds scattered over the marsh have not con- 

 fined themselves to one area, and the sHghtest disturbance has 

 frightened them to some other part, or has caused them to 

 leave the marsh altogether. About the end of March, how- 

 ever, certain birds arrive, in whose actions a difference is 

 noticed. They do not fly away at one's approach, or, if 

 frightened, soon return to the same spot. These birds do not 

 associate with the migrating flocks, and they roost alone. 

 If one is enabled to identify an individual bird among them 

 by such characteristics as abnormal feet or the loss of its tail 

 or a primary feather, as has frequently been done in this study, 

 one finds that it never changes its station in the marsh after 

 its arrival. Appearing about the last of March, these resident 

 males establish themselves at what are believed to be their 

 former nesting sites. To these spots they betake themselves 

 each afternoon, and from them they depart each morning to 

 the uplands where they feed during the day. Whatever time 

 is spent in the marsh, is spent at this station and nowhere else. 

 Many times between four and six o'clock in the afternoon, 

 ''marked" birds have been observed to enter the marsh along 

 with small groups of companions, which they soon left, pro- 

 ceeding directly to their chosen sites. The next morning, 



