PATTERNS OF LOCAL MOVEMENT 



the air it is seen as a complex pattern of shallow bays, connecting channels, 

 sloughs, and small potholes, all fringed with bulrush or cattail and set in a 

 matrix of Phragmites, the tall "yellow cane." 



Throughout the season, from spring break-up in April until freeze-up 

 in November, the Delta Marsh has its own population of waterfowl. Early, 

 this is made up mostly of breeding pairs, but soon bands of drakes that have 

 abandoned their nesting hens come to the big marsh for their molting pe- 

 riod. Here they don the drab eclipse plumage and become flightless, for 

 ducks, like geese and swans, lose the flight feathers of the wing all at once 

 and are unable to fly until new pinions are grown. Birds-of-the-year add to 

 local numbers; and before summer is old, many youngsters raised else- 

 where come to Delta. From early August until heavy frost there are constant 

 arrivals and departures, comings and goings, some birds staying only a few 

 days, others remaining weeks or months. 



Not one of these wildfowl finds that a given part of the marsh serves all 

 its needs. There may be a mile or more between the hen's nest and her terri- 

 tory. Most birds find their feeding, loafing, and graveling places at sepa- 

 rate locations, often far apart; and each may have more than one locality 

 for these activities. Some Mallards in late summer and autumn regularly 

 travel ten to fifteen miles from their loafing bars to the stubble fields, such 

 trips being made twice daily. Except during the flightless period, each 

 duck takes daily and often lengthy journeys within the realm of the marsh- 

 land. 



In the travel from marsh to lake, the local ducks cross the wooded ridge 

 at the same passes the transients used when they departed northward in mi- 

 gration. When a flock is flushed from the marsh, the birds seldom fly directly 



