TRADITIONS OF WATERFOWL 



that a period of three hundred years was available for the development of 

 the striking park dialect.' The significance of such nongenetic changes as 

 contributory factors to isolating mechanisms is evident (see also Cushing 

 1941)." 



Thorpe ( 1954) studied the pattern of the Chaffinch song by means of the 

 sound spectrograph and from this concluded that the normal song "has a 

 very restricted inborn basis." Some learning of song takes place during the 

 bird's early fife, but the final song form is acquired during a period of a few 

 weeks during the first spring. 



Nice (1943:264) says that "apparently the Song Sparrow recognizes 

 enemies by both inborn and learned patterns. In nature, the behavior of 

 the adults must be of great importance in the forming of conditioned pat- 

 terns in the young." She concludes that "experience may be handed down 

 non-genetically from generation to generation particularly in matters re- 

 garding protection from enemies." All evidence suggests that wild ducks 

 leam the nature of their relationship with man, fear or lack of fear being 

 transmitted from the experienced to the inexperienced. Hunters claim the 

 Mallard as the "wildest" of all ducks in autumn, the wariest, the most diffi- 

 cult to approach with gun. When young from wild eggs are reared in cap- 

 tivity, however, they are "tame" in the presence of man, showing no fear 

 of him.° This awareness of man as a "friend" is transmitted from one bird 

 to another, from flock to flock, until each year the number of fearless birds 

 of wild origin in the Delta pond is increased. We note the companion in- 

 fluence when a small band of Blue-winged Teal alights near the tame ducks. 

 As I approach these wild birds, they make departure movements. But when 

 their companions, who know me as a friend, show no escape reactions, the 

 wild birds remain; and although they are obviously more nervous, they 

 usually do not take flight. In a few days they may be approached on the 

 pond as closely as any of the old residents and are completely "settled 

 down." 



Surely some birds are tied traditionally to certain places. Not far from 

 Delta are the dancing grounds of a band of Sharp-tailed Grouse, which local 

 farmers recall as having been in regular use for at least sixty years. Al- 

 though many generations of grouse have come and gone, the living link of 

 action ties modern birds to the same plot of prairie as was used by their 



"And yet there is such a thing as "heritable wildness" (Leopold, 1944) in waterfowl. 

 When Mallard and Baldpate are hatched from wild eggs and reared by man in captivity, the 

 Baldpate, according to my experience at Delta, never becomes as tame or fearless of man as 

 the Mallard. 



224 



