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

other parameters. It should be notede that the sensitivity ranking shown in
figure 11.3.2 is relative for each season and therefore cannot be directly
compared between seasons.
A direct comparison of seasons for the assessment area, based on absolute
sensitivity values and averaged across all offshore areas, shows that winter
is most sensitive to oil spill (index value 48), closely followed by spring and
autumn (both value 46), while summer is least sensitive to oil spill (value
36). One general reason that winter, spring and autumn are relatively more
sensitive than summer, is the large number of wintering/migrating seabirds,
which all are very sensitive to oil (especially auks and seaducks). For more
details see the seasonal description below.
Spring (April/May-June)
Depending on the winter conditions the ice edge of the western pack ice
may still be present in the northern and western part of the assessment area,
but in early May there is normally open water throughout the area. As the
sea ice also disintegrates and retreats elsewhere, large numbers of wintering
auks and seaducks start migrating out of the assessment area towards breeding
areas north, west or east of Southwest Greenland. Large numbers of surface
feeders (kittiwakes and fulmars) which winter further south also pass
through the assessment area on their way to breeding colonies further north.
While many bird species leave or pass through the assessment area during
spring, baleen whales move in from the south to use the assessment area as
part of their summer foraging area. They take advantage of the productive
upwelling areas of the banks and prey on items such as krill, capelin and
sandeels, which are especially important for the whales. Also in spring, large
schools of capelin and lumpsucker move towards the coasts, where they
spawn in the intertidal zone. This attracts both seabirds and marine mammals.
The sensitivity classification of the offshore areas (Fig. 11.3.2) shows that the
near-coastal offshore areas are classified as highly sensitive or extremely
sensitive to oil spills during spring. This is mainly due to the large numbers
of wintering/migrating birds and extensive human use. Especially the fishery
for northern shrimp and snow crab is important in the near-coastal offshore
blocks, but also hunting and small-scale fisheries. The offshore block
in the southwest corner of the assessment area is also classified as highly
sensitive to oil spill due to the extensive Greenland halibut fishery (Fig.
5.1.3) and whelping areas for hooded seals in the western pack ice in March
and April.
Summer (July-August)
For many of the same reasons as mentioned above for the spring period, baleen
whales, human use of northern shrimp and snow crab and seabirds, the
near-coastal offshore areas are classified as highly sensitive or extremely
sensitive to oil spills during summer (Fig. 11.3.2); although relatively less
than during the other seasons (see above). Even though most wintering
birds now have left the assessment area, there is still a variety of breeding
birds (around 20 species), which largely forage in offshore areas. In addition,
over-summering (non-breeding) seabirds utilise the shelf areas and other
non-breeding seabirds utilise near-coastal areas during moulting.
223