The State of Circumpolar Walrus Populations

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13 haulout sites in the summers of 2012, 2013, and 2015 counted 2,500, 2,130, and 950 animals respectively. In 2015 lots of drifting and fast sea ice was present, so walruses hauled on sea ice near the terrestrial haulout were also counted. Walruses in Franz Josef Land use a core network of haulouts but the numbers of animals on a site can vary widely from year to year. For example, on Apollonoff Island there were about 1,000 animals hauled out in mid-August 2012, whereas during the same period in 2013 only 2 males were hauled out. Haulouts such as Hoffman Island or Adelaida Island can have several hundred walruses hauled out one year and none the next. Kara Sea - Southern Barents Sea – Novaya Zemlya (KS-SBS-NZ) The genetic relationship between walruses that summer in the southern Barents Sea and adjacent Kara and White seas to other walrus populations is uncertain, as are their abundance and life history (Boltunov et al. 2010). Movement of walruses does occur within this region. Of 10 walruses satellite-tagged in August at the Vaigach Island haulout, 8 remained in the Pechora Sea, moving offshore from the haulouts in early November as the sea ice formed; 2 entered the Kara Sea and travelled to the North Island of Novaya Zemlya (Semyonova et al. 2015). Of the latter, one travelled 935 km in 10 days before its tag stopped transmitting, the other travelled farther to haul out on the Oranskie Islands. Tag life ranged from 2 to 172 days. Male walruses sampled at the Vaigach Island haulout were genetically similar (mtDNA haplotypes) to Atlantic walruses from Svalbard but different from those of Greenland and from Pacific walruses (Shitova et al. 2014a; Semyonova et al. 2015). Male walruses sampled at Oranskie Island (n=8) were genetically similar to walruses (3 female, 6 male) from Franz Josef Land (Shitova et al. 2014b). Samples from female walruses, and more samples from Oranskie Island are needed for more representative comparisons. The southeastern arm of the Barents Sea (Pechora Sea) is shallow, with high production of the benthic prey species preferred by walruses. A recent survey has shown that this region provides important summer habitat for Atlantic Walruses, and earlier observations suggest that it might also be a wintering area (Lydersen et al. 2012:1555; see also Semyonova et al. 2015). Atlantic walruses used to live in the southwestern arm of the Barents Sea (White Sea), which is within the boreal zone and seasonally ice-covered, but were extirpated by hunting (M. Gavrilo, pers.comm.). In August 2011, an aerial photographic survey of 2,563 km of Pechora Sea coastline counted 968 walruses (Lydersen et al. 2012; Chernook et al. 2012). The animals were hauled out at a site on Vaygach (various spellings, e.g., Vaigach) Island (Cape Lyamchin Nos; 405 walruses) and two sites on Matveyev (various spellings, e.g., Matveev) Island (184 and 379 walruses), and all
14 appeared to be male. Crude measurements of dorsal curvilinear lengths (N = 504) showed that 85.5% were adults and the remainder juveniles (< 225 cm). When an adjustment factor developed for male walruses in Svalbard (Lydersen et al. 2008) was used to account for animals in the water during the survey, the number occupying this area was estimated at 3,943 (95% CI = 3,605– 4,325). This is the first estimate of walrus abundance in the Pechora Sea. The absence of females with calves suggests that the population is substantially larger, with a summer distribution that extends outside the survey area. Haulouts in the Matveev, Golets, and Dolgii (various spellings, e.g., Dolgiy) islands area are occupied from July until late November depending upon ice conditions (Glazov et al. 2013). Walruses leave the haulouts as soon as the ice is strong enough to support their weight. Heavy summer use of the area between Vaigach Island and Matveev Island, and October use of waters west of Matveev Island to the Gulayevskiye Koshki shoals suggests that these are important feeding area for walruses. These areas, which include the Nenetsky Nature Reserve, are perhaps the most important area of the Pechora Sea for walruses (Semyonova et al. 2015). In April 2014, an aerial survey (helicopter) yielded a preliminary estimate of 3,117 (SE 0.388) walruses on the ice of the Pechora Sea (Semyonova et al. 2015). This estimate was not based on a systematic survey and relies heavily on extrapolation based on habitat similarity. All sex and age groups of walruses, including females with calves of different ages, were seen during the spring survey but in summer Pechora Sea haulouts were occupied primarily by mature males (Semyonova et al. 2015). The summer distribution of females with calves is not yet clear but limited encounter and satellite tracking data suggest they may use the coastal waters of Novaya Zemlya on both the Kara and Barents Sea sides. Trend in abundance of Pechora Sea walruses cannot be established from the available survey data. However, since the first haulouts were reported from mainland coast and Matveev - Dolgiy Island in the 1990s (Isaksen et al. 2000; Goryaev et al. 2006) more haulouts and larger herds have been reported (M. Gavrilo, pers. comm.). In August 2013 an aerial survey of the mainland and western part of the Kara Sea, conducted in preparation for exploratory drilling, counted 1,355 walruses (Chernook et al. 2014; Semyonova et al. 2015). Most were hauled out on Vaigach Island (Cape Lyamchin Nos; 897) on the Barents Sea side, or swimming near the Oranskie Islands (250) or Gemskerk Island (185) which are situated near Severny Island (variously spelled Severniy and Severnyi) at the northern tip of the Novaya Zemlya Archipelago. Females with calves were present at haulouts in the archipelago, unlike those in the Pechora Sea. Terrestrial observations in the summers of 2012 to 2014 found walruses using the Vaigach Island (Lyamchin Peninsula) haulout on each of the 28 observation days, but their
Page 1 and 2: REPORT © Mikhail Cherkasov / WWF-R
Page 3 and 4: 2 ABSTRACT The walrus (Odobenus ros
Page 5 and 6: 4 PURPOSE AND SCOPE The WWF Arctic
Page 7 and 8: 6 beginning ca. 50,000 yBP that lim
Page 9 and 10: 8 Walruses from the Foxe Basin stoc
Page 11 and 12: 10 al. 2003). These differences coi
Page 13: 12 under favourable environmental c
Page 17 and 18: 16 comparable data for proper asses
Page 19 and 20: 18 (Fay 1982). The walruses that ar
Page 21 and 22: 20 A joint U.S.-Russia survey, with
Page 23 and 24: 22 for the conservation of walruses
Page 25 and 26: 24 provisions for walrus protection
Page 27 and 28: 26 northwestern and northeastern Gr
Page 29 and 30: 28 Franz Josef Land was discovered
Page 31 and 32: 30 USFWS 2014). The population is c
Page 33 and 34: 32 they return from hunting trips (
Page 35 and 36: 34 The USFWS has also developed gui
Page 37 and 38: 36 how many walruses are represente
Page 39 and 40: 38 (www.iucn.org/about/). The IUCN
Page 41 and 42: 40 Atlantic Walruses In Canada, the
Page 43 and 44: 42 Pacific walruses The primary sou
Page 45 and 46: 44 Foxe Basin (BIMC 2012). It has b
Page 47 and 48: 46 define shipping channels, season
Page 49 and 50: 48 Alaska may be a successful manag
Page 51 and 52: 50 of the population (Born et al. 1
Page 53 and 54: 52 In the Bering and Chukchi seas,
Page 55 and 56: 54 Garlich-Miller et al. (2011) ass
Page 57 and 58: 56 Hamilton et al. (2014) assessed
Page 59 and 60: 58 Canadian High Arctic - Northwest
Page 61 and 62: 60 2014a, b; Lindqvist et al. 2016)
Page 63 and 64: 62 reproduction and survival rates,
Page 65 and 66:
64 Jurisdictions with walrus popula
Page 67 and 68:
66 REFERENCES Allen, J.A. 1880. His
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68 Boertmann, D., A. Mosbech, D. Sc
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70 Chernook, V.I., C. Lydersen, D,M
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72 Durner, G.M., D.C. Douglas, R.M.
Page 75 and 76:
74 Galicia, M.P., G.W. Thiemann, M.
Page 77 and 78:
76 Environmental Ltd., Edmonton AB
Page 79 and 80:
78 Collection of scientific papers
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80 University of Guelph, Ontario, C
Page 83 and 84:
82 Noren S.R., M.S. Udevitz, and C.
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84 Phillipa, J.D.W., F.A. Leighton,
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86 Shitova M., M. Babushkin, A. Bol
Page 89 and 90:
88 Swenson, J.E., A. Bjørge, K. Ko
Page 91 and 92:
90 Witting, L. and E. Born. 2014. P
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92 Figure 2. Atlantic walruses in F
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Figure 4. Map of Atlantic walrus po
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TABLES Table 1. Assessment of Atlan
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98 Population 1 Stock or area 2 Sto
Page 101 and 102:
100 Table 2. Assessment of Pacific
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102 Table 3. Conservation status of
Page 105 and 106:
104 Table 4. Summary of primary wal
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106 Country Subspecies Hunt managem
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Page 111 and 112:
Page 113 and 114:
112 Subspecies Population 1 Knowled
Page 115:
114 Subspecies Population 1 Knowled
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The State of Circumpolar Walrus Populations

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