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

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(Mosbech et al. 2004b). The recovery time of such an event is unknown, as it
is still unknown whether each fjord hosts a separate genetically isolated
stock or if they mix. Additionally within the assessment area, only the near
coastal shelf area is of importance to capelin and here capelin is not as vulnerable
as they are highly mobile. Furthermore, because they are pelagic
feeders they are not as susceptible to long-term effects as benthic feeders.
Sandeel, Ammodytes spp.
Biology: Sandeels (or sand lance) are small bentho-pelagic fish with a central
position in many marine food webs. Two species occur in Greenland: the
lesser sandeel (Ammodytes marinus) and northern sandeel (A. dubius). They
are extremely similar and difficult to distinguish, and most surveys have
recorded sandeels simply as Ammodytes spp. Where they occur in high
abundance, sandeels are typically a key prey for many seabirds, marine
mammals and larger fish species. They feed on zooplankton in the pelagic
zone, mainly copepods, particularly Calanus finmarchicus. Sandeels spend a
large part of their time buried in sandy sediments and are most active during
the night, when they swim into the water column to feed. Most of the
feeding occurs during spring and summer. Sandeels are thus habitat specialists,
and the highest abundances are found on major sand banks at up to 100
m depth. However, smaller areas with suitable sandy sediments, e.g. around
islands where currents are strong, are also likely to be sandeel habitat.
Distribution: During a large sandeel survey in 1978, exploring the potentials
for a commercial fishery in Southwest Greenland, the highest sandeel concentrations
were found at the western and southern edge of Store Hellefiskebanke
(just north of the assessment area), at the southern edge of
Toqqusaq Banke (just north of Fyllas Banke), at Fyllas Banke and Fiskernæs
Banke (Andersen 1985). During a benthic cruise in 2009 very high densities
of sandeels (on average 9 indv. m -2 ) were found at Store Hellefiskebanke (J.
Hansen, unpubl.), but no sampling was done within the assessment area. Information
about the occurrence of sandeel larvae is available from zooplankton
surveys conducted in June-July in the period 1950 - 1984 (Pedersen &
Smidt 2000). The larvae were found throughout most of the shelf in the assessment
area, with the highest abundance at Fyllas Banke, Sukkertoppen
Banke and Lille Hellefiskebanke (see also section 4.2.5 and Fig. 4.2.4).
Sensitivity and impacts of oil spill: Being habitat specialists, sandeels are very
sensitive to localised oil spills, particularly if the oil settles on the sea floor.
As several important sandeel locations are known from the shelf area, there
is no question that the assessment area is a critical area for sandeels in West
Greenland. Earlier studies indicated that sandeels off West Greenland
spawned during the summer (Andersen 1985), but more recent studies have
found abundant young larvae during summer (Munk et al. 2003, Simonsen
et al. 2006), indicating mean hatching dates around 1 May. Given the expected
large biomass of sandeels in some parts of the assessment area, and
their central role as prey for a variety of species, impacts on sandeels have
the potential to indirectly affect a large part of the ecosystem.
Redfish, Sebastes mentella and Sebastes marinus
Biology: Four species of redfish live in the North Atlantic but only deep-sea
redfish (Sebastes mentella) and golden redfish (Sebastes marinus) are common
in West Greenland waters (Moller et al. 2010). Both deep-sea redfish and
golden redfish are highly valuable commercial species. Survey indices for
both redfish species combined in the Greenland shrimp survey varied be-