The Greenland White-fronted Goose Anser albifrons flavirostris

2Limits to population size in recent historical times
2.1 Current taxonomic status
The Greater White-fronted Goose Anser albifrons
is one of the most widely distributed large waterfowl
species in the arctic (Ploeger 1968, Ely &
Dzubin 1994). Four forms are currently recognised
as sub-species around the arctic region (see Figure
2.1 and discussion below).
Coburn (1902) was the first to suggest that the
White-fronted Geese in western Ireland more resembled
those that wintered in North America
than those in Europe. Nevertheless, it was as recently
as 1947 that Christopher Dalgety and Peter
Scott first described the White-fronted Geese
wintering in Ireland, Scotland and Wales as a new
race distinct from the European White-fronted
Goose Anser a. albifrons. The new subspecies they
named the Greenland White-fronted Goose Anser
albifrons flavirostris (Dalgety & Scott 1948). This
Figure 2.1. Breeding distribution of currently recognised White-fronted Goose
subspecies, flavirostris (Greenland), frontalis (Nearctic and Eastern Palearctic),
gambelli (Alaska) and albifrons (Palearctic), based on Cramp & Simmons (1977)
and Ely & Dzubin (1994).
form is one morphologically distinct group from
the circumpolar distribution, which extends from
the central Canadian arctic (west of Hudson Bay)
through to Alaska, and from the far east of Russia
to the Kanin peninsula (Figure 2.1).
Although there remains considerable discussion
about the precise taxonomic relationships, most
authorities agree that the breeding range of the
nominate race extends from the Kanin peninsula
to the Kolyma river in tundra Russia (Cramp &
Simmons 1977, Mooij et al. 1999). To the east of
this, it is replaced by frontalis in Russia, which
winters in the eastern Palearctic. This sub-species
also breeds across North America and winters in
Mexico and along Gulf and Pacific coasts (Ely &
Dzubin 1994). However, intensive studies from
the Pacific flyway show that allopatric Alaskan
breeding groups maintain temporal separation on
staging and wintering areas which has probably
contributed to the evolution
of previously described
phenotypic differences between
these populations
(Orthmeyer et al. 1995, Ely
& Takekawa 1996). These
authors suggest that these
sub-populations, along with
the Tule White-fronted
Goose (A. a. gambelli which
breeds in Cook Inlet, Alaska
in the taiga zone and winters
in Oregon and California),
may represent part of
a 'Rassenkreis', a group of
subspecies connected by
clines. Such a situation is
maintained over time
through limited but regular
genetic exchange between
units otherwise segregated
in time and space. Hence,
the internal genetic uniformity
of the existing taxonomic
units is unlikely to be
as simple as the current
sub-species structure might
suggest. Nevertheless, in
this respect, flavirostris remains
amongst the most
geographically isolated
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