LAMBECK RHD (1981) The present status of the Spitsbergen/Franz Josef Land population of the Pale-bellied Brent Goose Branta bernicla hrota. LIMOSA 54 (2): 52-56.

Pale-bellied Brents Branta bernic/a hrota occur more often than hitherto assumed in the Netherlands, outside their present wintering range, i.e. Denmark and NE England. In winter 1978 - 1979 they were, relatively speaking, rather common: a southwestward movement of probably hundreds of hrota had been initiated by a severe coldspell.
      So far the spring flock at Nissum Fjord (Denmark), with peak numbers around May I, is supposed to represent the whole population of Spitsbergen and Franz Josef Land. However, during an investigation in 1976 it was found that even in May several hrota were present in the Dutch Wadden Sea. It may be expected that in spring 1979 in any case part of the more southerly wintering hrota stayed in the Wadden Sea too. No May observations on Wadden Brents are available, but some April records point in this direction. Much more indicative, however, is the drop in peakcount number at Nissum Fjord between May 1978(2200) and May 1979 (1800 birds), despite the good 1978 breeding season.
      It is suggested that each year a non-negligible part of this hrota-population spends spring-time in the Wadden Sea. They are easily overlooked because of their relatively low and scattered numbers between the big majority of Dark-bellied Brents B. b. bernicla. This implies an underestimation of the present population size by some 5-10% in normal winters if Dutch data are representative for the whole Wadden Sea. The underestimation of the population by Nissum Fjord counts may be more important if the numbers of hrota in the Wadden Sea increase towards Denmark.
      A survey of available population data between 1966 and 1979 is given (tabel I). Contrary to bernic/a, protection has not resulted in an increase so far. However, signs of recovery may have been obscured owing to the problems in obtaining complete population counts. It is emphasized that such a recovery takes many years, considering the small size of the population (c. 2-3000 birds), the late sexual maturity and, in particular, the frequent breeding failures. In theory the southern hrota can drain the population by mixing up with the bernicla. However, they behave quite independently and mixed pairs are rare. Such a loss is probably unimportant.
      Although the practical problems are recognized, the delicate position of this population calls for a more comprehensive counting scheme. Additionally, annual age-ratio estimates are necessary for a better insight into the well-being of the hrota-population of Spitsbergen and Franz Josef Land. Pale-bellied Brent Goose Branta hrota = Branta bernicla hrota

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