OVERDIJK O & HORN H (2005) Breeding Eurasian Spoonbills Platalea leucorodia in the Netherlands in 1999-2004. LIMOSA 78 (3): 97-102.
The Netherlands is a core breeding area for
Eurasian Spoonbill in NW-Europe. This paper
reviews the developments in the breeding population
over the period 1999-2004. The number
of breeding pairs increased from 1010 in 1999
to 1749 in 2004. Simultaneously, distribution of
colonies expanded and in 2004 29 sites were
occupied (Fig. 2). Nearly 70% of the population
breeds on the (relatively predator-free) Wadden
Sea islands, especially Texel, Vlieland, Terschelling
and Schiermonnikoog. Further core
breeding sites are situated in the surroundings
of Lake IJsselmeer (notably Oostvaardersplassen)
and in the Delta Area in the SWNetherlands
(mainly Quackjeswater). At some
sites mixed breeding with Black-crowned
Night Heron Nycticorax nycticorax, Great Egret
Casmerodius albus and Little Egret Egretta
garzetta occurs. Reproduction varied greatly
among colonies and between years (Tab. 1, 2).
In larger colonies, reproduction tends to level
off, indicating colonies becoming saturated.
Colonies on some Wadden Sea Islands were
flooded during stormy weather in the breeding
seasons of 2001-2002. Another cause for lower
reproductive output might be poor weather.
During cold and wet periods, adults have difficulties
in finding food and simultaneously protecting
their offspring from heavy rains.
The increase in the Netherlands is paralleled
by population trends elsewehere in NWEurope.
The largest increase was observed in
the German Wadden Sea, with eight colonies
and 117 breeding pairs in 2003. New settlements
were also observed in Belgium (three in
2003) and France (five in 2003) whereas the
two colonies in Denmark persisted in 1999-
2003. A breeding attempt was reported from
the UK in 2002. At least in Germany, Denmark
and France breeding birds of Dutch origin (individually
marked with colour rings) have been
reported. Therefore it is likely that at least part
of the increase observed in NW-Europe, from a
total of 2200 pairs in 10 colonies in 1980 to
3200 pairs in c. 55 colonies in 2003, originates
from the growing Dutch population.
Currently a new monitoring and ringing
scheme is being developed for the breeding
population in Central and Eastern Europe (the
Pannonian flyway). All resightings of marked
birds, both from eastern and western European
populations, can be send to the authors (address
above).
Eurasian Spoonbill Platalea leucorodia
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