The Greenland White-fronted Goose Anser albifrons flavirostris

1 Introduction
1.1 Why Greenland White-fronted
Geese?
At the time when we first became interested in
Greenland White-fronted Geese, it looked as if
this race of the circumpolar White-fronted Goose
was in trouble. It was one of the few wildfowl
species wintering in Britain and Ireland that
lacked adequate annual census data to determine
the trends in its population size. Such information
as existed at that time strongly suggested
declines and extinctions at wintering resorts
throughout its range, especially in Ireland. Like
many migratory waterbirds at the time, it was
hunted throughout its entire range. Many features
of this little population made it attractive to study:
its breeding grounds in west Greenland were
hardly known to Europeans, although first details
of its breeding biology had been described
as long ago as 1950. It was known that some birds
at least staged in Iceland, but very little was
known about what the geese did there or the biological
significance of stopover staging there during
migration to and from the breeding grounds.
Finally, it was believed that the entire world population
wintered in Ireland and western Britain,
along the Celtic fringe of the European landmass.
Here, its use of boglands and low intensity agricultural
land in areas with some of the lowest
human population densities on those crowded
islands meant that its precise distribution and
abundance remained poorly known. Little wonder,
therefore, that this race of geese attracted the
attention of a dedicated band of students, all naively
intent on discovering 'the secret' of its decline.
The population had all the ingredients for
an exciting investigation – a declining population
of birds using remote (and naturally beautiful!)
landscapes in a relatively restricted part of the
globe! How could anyone not be intrigued by the
prospect?
1.2How much more do we know after a
period of study?
Twenty years on, we know a great deal more, but
we are still very far from an adequate understanding
of the ecology of the Greenland White-fronted
Goose. We are now more confident that the population
breeds exclusively in west Greenland
(MS23, MS24), stages on spring and autumn migration
in southern and western Iceland (MS4,
MS15, MS16, MS18, MS19, MS25, MS26, MS27)
and winters at some 70 regular winter haunts in
western Britain and Ireland (MS14, Figure 1.1). It
has proved possible, through international cooperation,
to co-ordinate an annual census of the
population on the wintering grounds and to sample
age ratios in order to assess changes in productivity
and monitor crude changes in survival.
Satellite transmitter devices have been deployed
on a sample of birds captured in Ireland to follow
the precise timing, staging areas and routes
taken by geese on migration to and from the
breeding and wintering grounds (MS20). We
know a great deal more about the breeding biology
and summer ecology of the population
thanks to summer expeditions to the breeding
grounds in 1979 and 1984 (Fox & Stroud 1981a,
MS1, MS2, MS3, MS5, MS24). Based on continuing
individual marking programmes, we now
have long term monitoring of annual survival rate
estimates (MS6, MS10), individual behaviour
Figure 1.1. Current wintering distribution of Greenland
White-fronted Geese in Ireland and Britain (from Fox
et al. 1999). Although dating from 1993/94, the distribution
has not changed (in terms of the flock size intervals
shown on the map) in the interim. Open symbols
indicate regular wintering sites currently abandoned
(map generated using DMAP).
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