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

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is mainly found between approx. 66° 30' N and approx. 70° 30' N and between
the coast and approx. 56° W (Born et al. 1994, Born et al. 1995).
During the mating season (January–April; Born 2001, Born 2003 and
references therein) male walruses engage in ritualised visual and acoustical
display underwater (Fay et al. 1984, Sjare & Stirling 1996, Sjare et al. 2003).
Delineation of population: Genetic analyses indicate that three subpopulations
exist in the Baffin Bay-Davis Strait region (Cronin et al. 1994, Andersen et al.
1998, Andersen & Born 2000, Born et al. 2001, Andersen et al. 2009a,
Andersen et al. 2009b, NAMMCO 2009): The (1) Eastern Hudson Bay-
Hudson Strait, (2) West Greenland-Southeast Baffin Island, and (3) and the
northern Baffin Bay stock confined to the North Water Polynya. The studies
indicated that (1) walruses in the West Greenland-Southeast Baffin Island
and the Baffin Bay populations differ genetically with some likely limited
male mediated gene flow between these populations, (2) walruses at Southeast
Baffin Island and West Greenland do not differ genetically, (3) walruses
from Hudson Strait have some genetic input to this West Greenland-
Southeast Baffin Island stock.
A satellite telemetry study during 2005-2008 supported the findings of the
genetic studies that walruses in West Greenland and at southeastern Baffin
Island constitute the same population, and this population is hunted in both
Greenland and Nunavut (NAMMCO 2009, Dietz et al. 2010).
Distribution: From October–November until late-May (timing varying from
year to year depending on sea ice conditions) walruses from the West Greenland-Southeast
Baffin Island stock (NAMMCO 2009) are found in the pack
ice approximately 30 to 100 km off the coast between approx. 65° 30' N and
approx. 68° 15' N. The main distribution in this region is north of approx. 66°
30’ N; although direct observations, satellite tracking and catch reports indicate
that walruses do occur inside the northern part of the assessment area
(Born et al. 1994, GINR/NERI unpubl. data).
Several systematic aerial surveys conducted during 1981–2008 (Born et al.
1994 and references therein, Mosbech et al. 2007, NAMMCO 2009, Heide-
Jørgensen et al. 2010a) showed that winter distribution of walruses off Central
West Greenland is similar to that indicated by historical information,
with two main concentrations; the shallow water banks between approx. 66°
30' N and approx. 68° 15' N, and the banks along the western coast of Disko
Island between approx. 69º 15' and approx. 70º 30' N (Ibid.).
On their West Greenland wintering grounds walruses prefer areas with
dense pack ice (usually more than 60% ice cover) in