The Greenland White-fronted Goose Anser albifrons flavirostris

sandy substrates which were the first to thaw
(MS1, Madsen & Fox 1981, Glahder 1999). These
storage organs, relatively rich in carbohydrates
and protein, were available to foraging geese long
before the onset of green above ground primary
production.
Once growth of such cyperacean plants starts,
there is a rapid decline in absolute and relative
quantities of storage polysaccharides and sugars
(Shaver & Billings 1976) as well as nitrogen and
phosphorous (specifically in E. angustifolium, Chapin
et al. 1975). Hence, Greenland White-fronted
Geese need to exploit this food resource immediately
the thaw enables its extraction from the
substrate, but before growth starts and quality
rapidly declines. Climate change and the timing
of migration therefore could have considerable
implications for the ability of geese to exploit subterranean
plant storage organs during the prenesting
period (and potentially at other times of
years also) as patterns of spring thaw become
modified. Geese arriving too early are unable to
extract plants from a frozen substrate, those arriving
too late encounter food of diminished and
declining quality.
With almost continuous daylight and the protection
of their attendant gander, female geese fed
for 68-82% of the 24 hour period on these high
quality foods for 10-19 days prior to clutch initiation
(MS1, Fox & Madsen 1981, Glahder 1999).
The period required for rapid oocyte development
in Alaskan White-fronted Geese A.a.frontalis
is considered to be 11-14 days (Ely 1979). Hence,
arriving geese are not only in a position potentially
to modify first egg dates given arrival conditions,
but also to accumulate substantial stores
during this prelude to breeding.
5.3 Potential effects of differential
staging within West Greenland
Based on studies undertaken in the southern part
of the breeding range, satellite telemetry (MS20),
observations of collared birds and other observations
all suggest that arriving pairs tended to congregate
in localised rich feeding areas which are
the first to thaw (MS1, Glahder 1999). At such
sites, there was an initial concentrated exploitation
of feeding resources, where females fed for
maximum uninterrupted periods and males
gained some extra feeding time by association
with groups of birds. Gradually, however, after
44
some 7 days, pairs split up and fed increasingly
away from other birds, ultimately dispersing from
the feeding aggregations close to ultimate nest
sites, but still feeding on plant storage organs
(MS20, Glahder 1999). In these situations, females
increased their abdominal profile index from a
median score of 1.5 to 2.5 between arrival on 4
May and 19 May, males increased from 1.0-2.0
over the same period (Glahder 1999). If the conversion
factor determined from correlation of API
and body mass in Iceland holds for the breeding
grounds, this would represent an increase of 228
g and 285 g of body mass respectively prior to
first egg date. Some of the increase in API amongst
females will correspond to the increase in the size
and extent of the ovaries and reproductive apparatus,
hence in this case it is unlikely that all the
increase in indices represents fat accumulation.
Nevertheless, this field score supports the observation
that this opportunity for pre-nesting feeding
provided an important period of recuperation
of used body stores.
Observations of collared birds moving within
west Greenland in spring 1984 (MS3) showed
geese may arrive and stage in one area and continue
elsewhere for the remainder of the summer.
Based upon the behaviour of the satellite birds,
in 1997, 1998 and 1999, geese arrived in west
Greenland between 3 and 17 May and staged at
arrival sites between Kangerlussuaq (66º30’N)
and northern Disko Bugt (69º50’N). Geese continued
to their ultimate summer areas after an
initial staging period of 9 days in 1998, but 16 days
in 1999. One of the geese staged in the central part
of the range before continuing to its summering
area on Svartenhuk Peninsula in 1998, and similar
patterns were witnessed in 1999, when the
prolonged snow cover meant potential feeding
and nesting areas in the north of the range were
inaccessible well into June (MS20, MS23). It would
therefore seem that in the favoured breeding habitat
around Kangerlussuaq (66º30’N) and further
north, the generally snow-free lowland wetlands
offer a food resource to staging geese that breed
locally and others that move northwards within
the summering range (MS1, MS2, MS3, MS20,
Glahder 1999, Glahder et al. submitted). It might
be expected that these local breeding birds have
access to earliest sources of food. However, as the
population has expanded, so these birds will have
faced increasing competition from the expansion
in their own numbers and of those breeding further
north that use the same spring staging areas.
Glahder (1999) showed by combining satellite