TRADITIONS OF WATERFOWL 



replace a 'burned out' breeding population or colonize a new area, a long 

 term value may be realized. But it cannot be considered sound management 

 to stock birds which do not survive long enough to reproduce." 



In the Mallard, heredity apparently plays an important role in the suc- 

 cess of plantings. The wild Mallard is the source stock from which the 

 "call" ducks and most domestic varieties originated, and the mixing of wild 

 and domestic blood may take place on game farm ranges. Such birds may 

 fail to survive or to migrate when released in a wild environment, and the 

 experience with such mixed strains prompted Lincoln (1934:81) to say 

 that "efforts to restore marshes with artificially produced Mallards are 

 doomed to failure." More recent investigations (Benson, 1939; Brakhage, 

 1953; Foley, 1954a; and Wells, 1954) suggest, however, that when hand- 

 reared Mallards are planted on wild ranges, the survivors of the first hunt- 

 ing season may migrate in a pattern not different from that of wild-bred 

 birds. At Delta we have found that hand-reared females return with un- 

 handed, wild-bred drakes as their mates. 



It is unfortunate that more attention has not been given in North 

 America to the artificial re-establishment of breeding traditions in some of 

 of the rarer species. The Trumpeter Swan, when reared by hand, breeds 

 well in captivity, and young from such hand-reared stock might be used 

 to repopulate locations where favorable breeding habitat still remains. The 

 species was captive-bred for many years in Europe, but unfortunately in 

 its own country there never has been a reservoir of hand-reared stock. And 

 I feel that it is only through captive-breeding that the Whooping Crane 

 can be saved from extinction, for the hazards of the long, traditional jour- 

 ney may be too dangerous for the few young that are produced each year. 

 The old birds, of course, must be left to follow their migration to and from 

 their northern breeding grounds, for adults would not breed in confinement. 

 But some young stock of these wild birds must be brought to captivity at 

 the earliest possible age and, under the care of trained "keepers," raised 

 where they may grow to maturity in a favorable, yet protected, environ- 

 ment. If this is done in time — if, at the rate of two or three young each 

 year, a captive breeding stock may develop in a protected situation — then 

 eventually some full-winged progeny of these long-lived birds may be set 

 free with the wild adults to learn from them the traditional flyways to and 

 from their ancestral breeding grounds. By captive-breeding the Wildfowl 

 Trust has given substantial increase to the numbers of the rare Hawaiian 

 Goose (Scott and Boyd, 1951, 1954, 1955). 



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