The Davis Strait - DCE - Nationalt Center for Miljø og Energi

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Kittiwakes are abundant in the shelf waters of the assessment area (Fig.
4.7.11) and many of these are non-breeding birds from populations breeding
elsewhere in the North Atlantic (Lyngs 2003). Kittiwakes spend the winter in
offshore parts of the North Atlantic, and at least some occur in the Davis
Strait, but very few were observed during the winter surveys in 1999
(Merkel et al. 2002).
Kittiwakes are most vulnerable to oil spills at breeding colonies where large
numbers of birds often assemble on the sea surface. There may also be concentrations
at feeding areas, e.g. in the marginal ice in spring and early
summer or at upwelling sites, but these are not predictable in time and
space.
Due to a substantial decrease in the breeding population (Labansen et al.
2010), the kittiwake is listed as Vulnerable (VU) on the Greenland Red List
(Boertmann 2007).
Ivory gull, Pagophila eburnea
Ivory gulls breeding in the northeast sector of the Arctic Atlantic (Northeast
Greenland, Svalbard and the Russian Arctic) move south in autumn in the
drift ice off East Greenland to winter quarters mainly in the marginal ice
zone in the Labrador Sea and the Davis Strait, where they arrive in December
(Orr & Parsons 1982, Gilg et al. 2010). This probably means that a large
proportion of the northeast Atlantic population of the ivory gull moves
through the assessment area in early December (Gilg et al. 2009, Gilg et al.
2010). In years when the drift ice in winter moves into the assessment area
from the west, ivory gulls will be present, but the fraction of the population
is unknown. In spring, most of the gulls probably move the same way back
through the assessment area; although it has been shown that they can migrate
northwards in the Davis Strait and across the Greenland Ice Sheet to
North East Greenland (O. Gilg pers. comm.). Observations from 2011 show
that adult ivory gulls are present in Julianehåb Bugt as early as late-October
(D. Boertmann, unpubl. data), a fact not revealed by the satellite-tracked
birds. Ivory gulls can probably therefore also be present in the assessment
area around this time or slightly later.
The ivory gull is of high conservation concern (Gilg et al. 2009, Gilg et al.
2010), being listed as near threatened (NT) on the international Red List
(IUCN 2011), as vulnerable (VU) on both the Greenland and the Svalbard
red lists (Boertmann 2007, Kålås et al. 2010), and as endangered by the
Committee on the Status of Endangered Wildlife in Canada (COSEWIC).
Iceland gull, Larus glaucoides
This gull is the most abundant of the large gulls in the assessment area. Numerous
breeding colonies are found there, on steep cliffs and small islands
(Fig. 4.7.2).
The assessment area is also an important winter habitat for this gull, and
both local breeding birds and birds from northern areas assemble here
(Lyngs 2003, Boertmann et al. 2006).
Iceland gulls are most sensitive to oil spills at the breeding colonies. These
colonies, however, are generally small and the population is spread widely
along the coasts and population sensitivity is therefore relatively low compared
to other much more concentrated seabirds.