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

4.9.1 Pelagic hotspots
The shelf bank areas (e.g. Fyllas Banke) and the shelf break are assumed to
have increased primary productivity in spring due to nutrient-rich
upwelling events from wind and tidal motions in the Davis Strait. There are
limited data in the assessment area, in terms of physical measurements on
primary productivity, to support this; however, remote sensing data
(MODIS, chlorophyll a) showing productivity in the surface layer clearly
identifies Fyllas Banke as the location for the initial spring bloom in March.
Results from the Nuuk Basic monitoring programme supports this. Productivity
peaks in April and May and occurs then more widely over the shelf
break and in neighbouring offshore areas.
The enhanced primary production retains zooplankton species such as copepods,
which again are utilized by fish larvae. In general, the slopes of the
shelf and shelf banks are believed to be important for fish larvae development
due to high biomass of their copepod prey. For Greenland halibut, the
main spawning ground is assumed to be located in the western part of the
assessment area and the eggs and larvae are known to drift through the assessment
area towards settling areas further north.
4.9.2 The tidal/subtidal zone
The tidal and subtidal zone is an important habitat for macrophytes, many
invertebrates, fish, marine mammals and seabirds. Among others, it provides
critical spawning and nursery habitat for capelin and lumpsucker.
Capelin is an ecological key species, important for larger fish species,
whales, seals, seabirds and human use, while lumpsucker support a smallscale
commercial fishery on lumpsucker eggs. The benthic macrofauna, such
as bivalves and sea urchins, play a key role for benthic feeders, such as
common eider, king eider and long-tailed duck.
In addition, the tidal/subtidal zone is very important for seabird hunting
and tourism.
4.9.3 Demersal fish and benthos
The sea floor and the adjacent parts of the water column support the commercially
important fisheries of Greenland halibut, northern shrimp and
snow crab. For Greenland halibut, the main spawning ground is assumed to
be located in the western part of the assessment area.
In addition, sandeels, which are the most important food for many seabirds
and whales, are distributed in high densities in sandy sediments at the shelf
banks (e.g. Fyllas Banke). Benthic macrofauna, such as bivalves and sea urchins,
also plays a central role for benthic feeders at the shelf banks, such as
king eiders, bearded seal and walrus. The sea floor and adjacent parts of the
water column are also important for cod, which sustained an important fishery
in the past and has the potential of becoming commercially important
again.
4.9.4 Breeding seabirds
For the common eider, black-legged kittiwake, Iceland gull, black guillemot,
common murre, Atlantic puffin and white-tailed eagle the coastal areas and
the fjords of the assessment area are important as breeding grounds. The
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