The Pochard Aythya ferina is essentially a breeding bird of freshwater habitats of the steppes, where it may nest even in very temporary saline, brackish or soda waters (Cramp & Simmons 1977). In the last 150 years, however, it has expanded its summer range into north and west Europe, this being initiated perhaps by drought in its shallow breeding lakes in Central Asia. Bezzel (1969) mapped th

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