The State of Circumpolar Walrus Populations

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from Clavering Island to the northern border of the Northeast Water yielded a fully corrected
summer estimate of 1,430 (CV = 0.45) walruses (Born et al. 2009). Modelling suggests this
population has recovered from its historical depletion but the trajectory of this recovery is
uncertain due to lack of a population specific growth rate estimate (Witting and Born 2014).
Svalbard – Franz Josef Land Population (S-FJL)
The Norwegian archipelago of Svalbard and Russian archipelago of Franz Josef Land share a
walrus population (Wiig et al. 2014; Figure 4). These animals are genetically similar (Andersen et
al. 1998; Born et al. 2001), move between the archipelagos (Wiig et al. 1996; Freitas et al. 2009;
Hamilton et al. 2015), and are separated from other walruses by wide distributional gaps (Born
1984; Born and Gjertz 1993; Gjertz and Wiig 1994). In 2010 an adult male that was genetically
similar to walruses in this population travelled from the Faroe Islands to Svalbard, a distance of
2216 km between 29 March and 25 April (Born et al. 2014). The relationship of Atlantic walruses
in this population to those in the Kara Sea - southern Barents Sea –Novaya Zemlya population is
uncertain (Born et al. 1995; NAMMCO 2006; Boltunov et al. 2010; Shitova et al. 2014b).
Walruses in Svalbard follow the same seasonal migration pattern regardless of annual variations
in ice and temperature regimes (Freitas et al. 2009). Summer habitat use for both sexes appears
to be driven by feeding requirements and the availability of haulouts or sea ice. Most of the males
summer in Svalbard and most of the females and calves remain in northeastern parts of Svalbard,
in the Franz Josef Land archipelago, or between them on Victoria Island (Lydersen et al. 2008;
Gavrilo 2010; Kovacs et al. 2014; Wiig et al. 2014). To reach breeding areas the males actively
travel through areas of dense ice cover towards Franz Josef Land in winter, regardless of sea ice
advances and retreats (Freitas et al. 2009).
Walruses in Svalbard were protected from harvesting in 1952 after having been brought to the
brink of extinction by 350 years of unregulated removals (Anon. 1952; Kovacs et al. 2014). Prior
to commercial hunting the population must have been very large (Reeves 1978; Gjertz et al. 1998;
Weslawski et al. 2000). During the first 30 years of protection, about 100 animals became
established within the archipelago. They are presumed to have come from Franz Josef Land to the
east. Since then a marked recovery has occurred in the abundance of walruses in Svalbard.
Systematic surveys that covered all current and historical haulout sites were flown in August 2006
(Lydersen et al. 2008) and late July to mid-August 2012 (Kovacs et al. 2014). The surveys,
adjusted to account for animals that were in the water, estimated there were 2,629 (95% CI =
2,318 – 2,998) walruses in the Svalbard area in 2006 and 3,886 (95% CI = 3,553-4,262) in 2012.
This represents an average annual increase of nearly 8% (Kovacs et al. 2014), which matches the
theoretical maximum rate of growth that has been calculated for recovering walrus populations