OUWENEEL GL VAN DER LINDEN A VAN DER LINDEN L & KOFFIJBERG K (2008) Behaviour and habitat preference of wintering Lesser White-fronted Geese Anser erythropus in the Oude Land van Strijen, SW-Netherlands. LIMOSA 81 (1): 17-23.
Since the start of the Swedish reintroduction scheme for
Lesser White-fronted Goose in the early 1980s, the wintering
numbers of this species in The Netherlands have
increased to about 100-120 individuals. There are six frequently
used staging sites in the northern and western
part of the country, within the commonly used flyway of
their foster-parent Barnacle Geese. The Oude Land van
Strijen, an open agricultural area and Special Protected
Area (SPA) of 1600 ha in the Dutch Delta area (Zuid-
Holland), is one of themost important sites and has been
visited nearly each winter from1987/88 onwards (Fig. 1).
Especially after 2002/03, larger numbers have been
counted (up to 78 individuals in 2007/08), coinciding
with significant earlier arrival and later departure dates
(Fig. 2). The Oude Land van Strijen has been a traditional
staging site for Greater White-fronted Geese and
Barnacle Geese since at least the 1950s. The first Lesser
White-fronted Geese in January 1988 were probably
brought to the area by their foster-parents. Until
2005/06, most LesserWhite-fronts (both originally introduced
and their wild offspring) usually stayed within
flocks of the other goose species, and also joined their
night-roost in the nearby Hollandsch Diep. However,
since larger numbers have started to visit the area, the
Lesser White-fronted Geese behave more independently,
including species-specific flight distances when disturbed.
Contrary to other goose species, Lesser Whitefronts
have always foraged on grassland, whereas other
geese also fed on arable harvest remains or autumnsown
cereals. They now often roost in one of the inundated
grasslands at night, in the absence of Greater
White-fronted and Barnacle Geese.
A detailed study in 2006/07, including counts at 2-3
day intervals and mapping of 97 Lesser White-fronted
Goose flocks (Fig. 3,4), revealed site use that is verymuch
restricted to specific parts of the polder (Fig. 4).
Especially after arrival in autumn, the birds gather in a
small area of about 20 ha. Later on, flocks disperse over a
wider range of fields, but often remain within close distance
(250 m) of the Dwarsche Vaart, an old stream that
runs through the area. This terrain is characterised by
damp fields with a dense network of small ditches,
trenches and hummocks. These damp and hummocky
fields to some extent resemble the breeding sites in
Sweden. A similar preference has also been observed at
another staging site, the Harger and Pettemerpolder in
Noord-Holland. Prolonged feeding in the trenches and
ditches (which can make the birds very difficult to find)
suggests that the birds find good feeding conditions
and/or wind shelter in these hollows.
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