Yalden, D. W & Parker, J. G / August 1994 – vol. 87, issue 8, pp 394–395 Those Ruddy Ducks. The status of the Ruddy Duck Oxyura jarnaicensis seems to be causing much heartache among birdwatchers at present (e.g. Brit. Birds 86: 338). The fact that it has started to hybridise with the small population of the endangered White-headed Duck O. leucocephala in Spain has prompted cries of anguish from the Spanish, who have done much to reverse the decline in the White-he... This article is only available to registered users.To read more, please log in or purchase a subscription.