KOOIJ H VAN DER & VOSLAMBER B (1997) Development of the Great White Egret Egretta alba population in The Netherlands in an European. LIMOSA 70 (3): 119-125.

There is no proof of historical breeding of the Great White Egret Egretta alba in The Netherlands. In this century, numbers sighted have increased since 1944 and the species has been recorded annually since 1970. This is mainly a result of embankment of the polder Zuidelijk Flevoland in Lake IIsselmeer. Established as a nature reserve within this polder in the 1970s, the Oostvaardersplassen played a key role in the return of the Great White Egret as a breeding bird in The Netherlands. First breeding probably occurred in 1977, and was proved in 1978 (four young fledged). In the 1980s, single breeding pairs were recorded almost every year, some consisting of mixed pairs with Grey Heron. Breeding success was poor. By the end of the 1980s, special management measures were taken in Oostvaardersplassen in order to regulate watertables. This lead to less turbid water and an abundance of small fish (mainly Three-spined Stickleback). As a result, one or two pairs of Great White Egret successfully bred each year. Five pairs bred in 1995, raising a total of nine young to fledging. However, when initial impact of watertable management disappeared, only one pair remained (1996).
      Elsewhere, one pair bred in Friesland province in 1981. Irregular breeding has occurred since 1991 in Naardermeer (North Holland province) and Nieuwkoopse Plassen (South Holland province). Breeding success is not known for most of these cases.
      A maximum of twenty birds has been counted in the Netherlands during the nonbreeding season. In some frequently used areas, birds are present each autumn. Patterns of the mean number of birds over the year in Oostvaardersplassen and elsewhere in The Netherlands are complementary, suggesting postbreeding dispersal of birds from Oostvaardersplassen.
      Numbers have increased as they did in colonies in Neusiedler See, Austria and at wintering sites along the river Po, Italy and Camargue, southern France. In both places, as well as at Lac de Grand-Lieu, France, small numbers have started to breed recently. This visually hunting species needs shallow and clear water with an abundance of fish. Such conditions will probably spread in The Netherlands, where several nature development projects are implemented. Other rare heron species may also benefit from these projects. Western Great Egret Ardea alba = Egretta alba

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