LAMBECK RHD (1981) Pale-bellied Brent Geese Branta bernicla hrota in the Delta area in winter 1978 - 1979. LIMOSA 54 (2): 47-51.

In winter 1978/79 a relatively large number, without recent precedent, of Pale-bellied Brent Geese Branta bernicla hrota was recorded in the Delta area (SW Netherlands). Normally hrota from Spitsbergen and Franz Joseph Land winters.in Denmark and NE England (Lindisfarne), although especially solitary birds reach the Dutch Wadden Sea and even the Delta area regularly. Obviously the very cold weather that started at the end of December forced part of the Danish birds southwestward. All records are given (bijlage 1) and migratory movements are discussed.
      The age ratio of the Jariuary/February hrota was lower than that of the March birds (2 juveniles out of 20 (10%) and 9 out of 27 aged birds (33%) respectively). The majority of the March juveniles formed part of (incomplete) families. Presumably these birds returned from winterhaunts in Britain or France. These data on hrota are consistent with the migratory behaviour of the Dark-bellied Brent Goose B. b. bernic/a: in the most important Delta area haunt the juvenile percentage dropped after the first cold spell from c. 35 to 18%, while overall numbers (c. 2000 birds) only slightly decreased.
      Based mainly on data on age and social status of part of the birds and, moreover, on the spread in numbers, localities and dates, it could be ascertained that at least 64 hrota have stayed in the Dutch Delta area, which is c. 3% of the Spitsbergen population. It is suggested that the actual number of birds was considerably higher since coverage was incomplete. Taking into account the many records elsewhere in the Netherlands it can be assumed that several hundred hrota took part in the southwestward movement Pale-bellied Brent Goose Branta hrota = Branta bernicla hrota

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