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

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spawns in spring (April-May). The eggs and later the larvae drift with the
currents and the larvae settle in the autumn at lengths of 5-7 cm. Temperature
has an impact on the abundance as well as the development and survival
of the eggs (Buckley et al. 2000).
Distribution and spawning stocks: The Atlantic cod found in Greenland is derived
from three separate ‘stocks’ that each is labelled by their spawning areas:
I) historical offshore spawning grounds of East and West Greenland; II)
spawning grounds in West Greenland fiords; and III) Icelandic spawning
grounds where the offspring are occasionally transported in significant
quantities with the Irminger current to Greenland waters. The Icelandic offspring
generally settle off East and South Greenland, whereas offspring from
the Greenland offshore spawning is believed mainly to settle off the West
Greenland coast (Wieland & Hovgaard 2002). The assessment area is therefore
a potential nursery area for young cod originating from both the Icelandic
and the offshore Greenlandic stocks. Tagging experiments have
shown that the offshore stock occasionally migrates to the coastal zone and
mixes with the inshore stocks (Storr-Paulsen et al. 2004).
Lumpsucker, Cyclopterus lumpus
Biology: Mature lumpsucker adults (3-5 years of age) arrive along the Greenland
coastline throughout the assessment area in early spring (Mosbech et al.
2004b) and spawn in the following months in shallow waters (Muus &
Nielsen 1998). The male guards and ventilates the approximately 100,000-
350,000 eggs for a couple of months (Muus & Nielsen 1998, Sunnanå 2005).
Based on Norwegian data, the offspring probably spend the first two years
in the near shore kelp. The adult fish reside in deeper waters outside the
spawning season, but it is unknown if and to where they migrate outside the
spawning season. They are, however, occasionally caught in near shore shelf
areas in bottom trawls (Greenland Institute of Natural Resources, unpublished
data). The feeding behaviour of Greenland lumpsucker is unknown,
but due to its poor swimming capabilities it is most likely restricted
to jellyfish and other slow-moving organisms (Muus & Nielsen 1998).
Lumpsuckers may constitute a significant prey resource to sperm whales in
the area, as seen elsewhere (Kapel 1979, Martin & Clarke 1986).
Distribution: The common lumpsucker is distributed throughout the assessment
area, and also found at both higher and much lower latitudes (i.e.
North Sea). Hence, climatic changes will most likely not negatively affect the
lumpsucker in the assessment area through direct temperature effects. However,
as little is known about lumpsucker migrations and dependency on
other ecosystem components, it is unclear how the species would respond to
climatic changes.
Sensitivity and impacts of oil spill: Given the dependency of shallow waters
near coastal areas for spawning, the lumpsucker will be especially sensitive
to an oil spill on beaches in the spawning period. Other potentially important
areas, such as feeding areas, are not known. The overall sensitivity
of lumpsucker was estimated as moderate in an environmental oil spill sensitivity
atlas for the coastal zone in the area just south (60-62˚N) of the assessment
area (Mosbech et al. 2004b), and similar conclusions should apply
in this case.