Re-introduction of the white-headed duck to Kiskunsaog, Hungary

Summary

The white-headed duck (Oxyura leucocephala) went extinct in Hungary in the 1960s, with the last confirmed breeding at Lake Kondor in 1961. Starting in 1982, Hungarian aviculturalists trained by the Wildfowl and Wetlands Trust at Slimbridge, England, built a breeding centre at Fülöpháza, next to Lake Kondor, using seven rubber-lined ponds. Between 1984 and 1988, 162 eggs shipped from England were artificially incubated, but hatching success never matched Slimbridge's roughly 60 percent, peaking at 52 percent in 1988 after birds were separated into one-male, two-female breeding trios in 1987 to reduce aggression; success then declined and no eggs hatched after 1989, with rising rates of abandoned and infertile eggs attributed to inbreeding from only three founder pairs, egg predation by rats, and unresolved behavioral problems. The remaining captive birds were transferred to Budapest Zoo in 1992, where none bred and none survive today. In the field, 52 birds were released across three events between 1986 and 1988 at Lake Péteri and Lake Kondor, with a fourth 1991 release undocumented. Most released birds disappeared within two months; Lake Kondor dried out, forcing recapture of some, others dispersed into a hunting area and vanished, likely shot illegally, and neither release site proved ecologically suitable, with Péteri never a historic breeding site and Kondor lacking sufficient food. The project rated itself a Failure, stating plainly that it did not establish a population.