Mapping of potentially suitable maternal denning habitats for female polar bears on the archipelago of New Siberian Islands and development of their conservation proposals

The archipelago of New Siberian Islands is an important breeding area for the Laptev subpopulation of polar bear, which remains one of  the least studied in the Russian Arctic. Information on the number of dens established by breeding female polar bears is a significant parameter for estimating the size of the entire subpopulation, which has only rough expert estimates. Modeling potentially suitable maternal denning habitats is necessary for organizing censuses and subsequently estimating the number of  breeding females on the archipelago, as well as for developing scientifically-based conservation proposals. An analysis of landscape features, weather conditions, and ice conditions in the archipelago of New Siberian Islands revealed that the largest area of suitable denning sites is located in the northern part of the archipelago (Kotelny Island, Novaya Sibir Island, and Belkovsky Island). Climate change is unlikely to have a significant negative impact on the availability of denning habitats for breeding female polar bears of the Laptev subpopulation in the coming years. However, global warming may negatively impact the well-being of female polar bears and their cubs due to reduced food availability, the spread of more southern pathogens, and increased time spent on land. The State Nature Reserve “Novosibirsk Islands” (Novosibirskiye Ostrova) does not encompass all the habitats most suitable for denning; therefore, the measures proposed in this article contribute to  a  more comprehensive polar bear conservation on the archipelago.

1. Melikhova E.V., Belikov S.E., Gnedenko A.E., Chernyshova D.A. Modeling of Areas Potentially Suitable for the Denning by Breeding Polar Bear Females on Wrangel Island and the Coast of Chukotka. Environment protection and nature reserve management. 2022;(1):22–35. (In Russ.).

2. Gnedenko A.E., Belikov S.E., Belyavskii D.S. Modeling of Habitats Potentially Suitable for Dens by Breeding Female Bears on the Franz Josef Land Archipelago. Environment protection and nature reserve management. 2022;(3):25–32. (In Russ.).

3. Belikov S.Е., Gnedenko A.E., Plotnitskaya D.A. Modeling and mapping of potentially suitable habitats for dens of breeding female polar bears on the Severnaya Zemlya archipelago. Environment protection and nature reserve management. 2023;(3):5–12. (In Russ.).

4. Gnedenko А.Е., Belikov S.Е. Modelling habitats potentially suitable for dening of breeding female polar bears, on Novaya Zemlya Arkhipelago. In: XIII International conference «Marine research and education» MARESEDU-2024. Vol. I (IV). Tver: PoliPRESS Publ.; 2025, с. 259–263. (In Russ.).

5. Obbard M.E., Thiemann G.W., Peacock E., DeBruyn T.D. Polar bears: Proceedings of the 15th working meeting of the IUCN/SSC Polar Bear Specialist Group, 29 June-3 July 2009, Copenhagen, Denmark. Occasional Paper of the IUCN Species Survival Commission, No. 43. Switzerland and Cambridge, UK: International Union for Conservation of Nature, Gland; 2010.

6. Belikov S.E. Polar bear abundance, distribution and migrations in the Soviet Arctic. In: Novikov B.V., ed. Large predators. Moscow: CSRLof the Glavokhoty of the RSFSR; 1992, pp. 74–84. (In Russ.).

7. Karpovich V.N. Polar bear distribution in the Soviet Arctic according to the correspondent network. In: Polar Bear and its Conservation in the Soviet Arctic. Leningrad: Gidrometeoizdat Publ.; 1969, pp. 68–88. (In Russ.).

8. Kishchinskii A.A. A polar bear on the New Siberian Islands. In: Polar Bear and its Conservation in the Soviet Arctic. Leningrad: Gidrometeoizdat Publ.; 1969, pp. 103–113. (In Russ.).

9. Belikov S.E., Randla T.E. Fauna of birds and mammals of the Northern Land. In: Fauna of birds and mammals of Central Siberia. Moscow: Nauka Publ.; 1987, pp. 18–28. (In Russ.).

10. Uspenskii S.M. Polar bear. Moscow: Agropromizdat Publ.; 1989. (In Russ.).

11. Belikov S.E., Glazov D.M., Gnedenko A.E., Demyanets S.S., Isachenko A.S. Areas of the Russian Arctic with increased occurrence of key species of marine mammals and polar bears. Environment protection and nature reserve management. 2024;5(3):99–133. (In Russ.).

12. Uspenskii S.M. Polar bear. Moscow: Nauka Publ.; 1977. (In Russ.).

13. Uspenskii S.M., Chernyavskii F.B. Polar bear breeding point. Priroda. 1964;(4):81–86. (In Russ.).

14. Chelintsev N.G. Determination of the absolute number of dens based on sample counts. In: Polar Bear and its Conservation in the Soviet Arctic. Moscow; 1977, pp. 66–85. (In Russ.).

15. Belikov S.E., Stashkevich L.F., Gaev V.A. Polar bear ecology on Wrangel Island. In: Biological Problems of the North. Fauna of Wrangel Island. Vladivostok; 1986, pp. 127–134. (In Russ.).

16. Stishov M.S. The location and number of polar bear maternity dens on Wrangel and Herald Islands in 1985-1989. In: Animal populations and communities of Wrangel Island. Moscow; 1991, pp. 91–115. (In Russian).

17. Belikov S.E. Belyi medved’. V: Belikov S.E., Vaisfel’d M.A., Grachev Yu.A., et al. Bears: Brown bear, polar bear, Himalayan bear: Location of reserves, ecology, use and protection. Moscow: Nauka Publ.; 1993, pp. 420–478. (In Russ.).

18. Belikov S.E. Data on female polar bear denning on Wrangel Island. In: Ecology and morphology of the polar bear. Moscow: Nauka Publ.; 1973, pp. 28–36. (In Russ.).

19. Belikov S.E. Abundance, distribution, and den structure of female polar bears in a model area on Wrangel Island. In: Polar Bear and its Conservation in the Soviet Arctic. Moscow: Central Laboratory of Nature Conservation of the USSR Ministry of Agriculture; 1977, pp. 19–33. (In Russ.).

20. Kishchinskii A.A. Polar bear. Leningrad: Lesnaya promyshlennost’ Publ.; 1974. (In Russ.).

21. Belikov S.E. Polar bear of the Russian Arctic. In: Matishov G.G., Tishkov A.A., eds. Terrestrial and marine ecosystems. Moscow: Paulsen Publ.; 2011, pp. 263–291. (In Russ.).

22. Chinn S.M., Liston G.E., Wilson R.R. Assessing past and future climatic influences on the availability of polar bear maternal denning habitat on Wrangel Island. Ecological Modelling. 2023;484:110479. https://doi.org/10.1016/j.ecolmodel.2023.110479

23. Kochnev A.A. Distribution and Abundance of Polar Bear (Ursus Maritimus) Dens in Chukotka (Based on Inquiries of Representatives of Native Peoples). Biology Bulletin. 2018;45(8):839–846. https://doi.org/10.1134/s1062359018080058

24. Florko K., Derocher A.E., Breiter C-J.C., Ghazal M., Hedman D., Higdon J.W., Richardson E.S., Sahanatien V., Trim V., Petersen S.D. Polar bear denning distribution in the Canadian Arctic. Polar Biology. 2020;43:617–621. https://doi.org/10.1007/s00300-020-02657-8

25. Archer L.C., Kirschhoffer B.J., Aars J., James D.K., Miller K.M., Pilfold N.W., Sulich J., Owen M.A. Monitoring phenology and behavior of polar bears at den emergence using cameras and satellite telemetry. The Journal of Wildlife Management. 2025;89(3):e22725. https://doi.org/10.1002/jwmg.22725

26. Laidre K.L., Stirling I. Demographic response of a high-Arctic polar bear (Ursus maritimus) subpopulation to changes in sea ice and subsistence harvest. Endangered Species Research. 2020;51:73–87. https://doi.org/10.3354/esr01239

27. Pedersen N.J., Brinkman T.J., Shideler R.T., Perham C.J. Effects of environmental conditions on the use of forward-looking infrared for bear den detection in the Alaska Arctic. Conservation Science and Practice. 2020;2(7):e215. https://doi.org/10.1111/csp2.215

28. Smith T.S., Amstrup S.C., Kirschhoffer B.J., York G. Efficacy of aerial forward-looking infrared surveys for detecting polar bear maternal dens. PLoS ONE. 2020;15(2):e0222744. https://doi.org/10.1371/journal.pone.0222744

29. Wilson R.R., Durner G.M. Seismic survey design and effects on maternal polar bear dens. The Journal of Wildlife Management. 2019;84(2):201–212. https://doi.org/10.1002/jwmg.21800

30. Liston G.E., Gura K.B., Crawford J.A., Polasek L., Perham C.J., Quakenbush, L., et al. Modeling polar bear (Ursus maritimus) snowdrift den habitat on Alaska’s Beaufort Sea coast using SnowDens-3D and ArcticDEM data. Ecological Modelling. 2025;501:110939. https://doi.org/10.1016/j.ecolmodel.2024.110939

31. Polyakova E.V., Kutinov Yu.G., Mineev A.L., Chistova Z.B. Analysis of the applicability of the ASTER GDEM v2 and ArcticDEM digital elevation models in research on Russia’s Arctic territories. Sovremennye problemy distantsionnogo zondirovaniya Zemli iz kosmosa. 2020;17(7):117–127. (In Russ.). https://doi.org/10.21046/2070-7401-2020-17-7-117-127

32. Glennie C. Arctic High-Resolution Elevation Models: Accuracy in Sloped and Vegetated Terrain. Journal of Surveying Engineering. 2017;144(1). https://doi.org/10.1061/(asce)su.19435428.0000245

33. Boehner J., Antonic O. Land-surface parameters specific to topo-climatology. In: Hengl T., Reuter H., eds. Geomorphometry — Concepts, Software, Applications. Developments in Soil Science. Vol. 33. Elsevier; 2009, pp. 195–226. https://doi.org/10.1016/s0166-2481(08)00008-1

34. Hall D.K., Riggs G.A. Accuracy assessment of the MODIS snow products. Hydrological Processes. 2007;21(12):1534–1547. https://doi.org/10.1002/hyp.6715

35. All-Russian Research Institute of Hydrometeorological Information [internet]. Available at: http://meteo.ru/ (accessed 17 April 2025). (In Russ.).

36. Radionov V.F., Aleksandrov E.I., Bryazgin N.N., Dementiev A.A. Changes in temperature, precipitation and snow cover in the Arctic Sea region, 1981–2010. Ice and Snow. 2013;53(1):61–68. (In Russ.). https://doi.org/10.15356/2076-6734-2013-1-61-68

37. Sosnovsky A.V., Osokin N.I. The snow depth and its dynamics on the continental part of the Russian Arctic under conditions of the present-day climate. Ice and Snow. 2024;64(2):238–251. (In Russ.). https://doi.org/10.31857/S2076673424020074

38. Afanas’eva E.V., Alekseeva T.A., Sokolova Yu.V., Demchev D.M., Chufarova M.S., Bychenkov Yu.D., Devyataev O.S. AARI methodology for sea ice charts composition. Russian Arctic. 2019;(7):5–20. (In Russ.). https://doi.org/10.24411/2658-4255-2019-10071

39. Liang H., Zhou W.Arctic sea ice melt onset in the Laptev Sea and East Siberian Sea in association with the Arctic Oscillation and Barents Oscillation. Journal of Climate. 2023;36(18):6363–6373. https://doi.org/10.1175/JCLI-D-22-0791.1

40. Zhang C., Zhang Z., Qi P., Zhang Y., Dai C. Analysis of the effect of sea surface temperature on sea ice concentration in the Laptev Sea for the years 2004–2023. Water. 2025;17(5):769. https://doi.org/10.3390/w17050769

41. Kraineva M., Golubeva E. Formation of heat anomalies in the Laptev Sea (2000-2020 years). In: Chaplina T., eds. Processes in GeoMedia. Vol. V. Springer, Cham; 2022, pp. 169–178. https://doi.org/10.1007/978-3-030-85851-3_19

42. Bliss A.C., Comiso J.C., Parkinson C.L., Gersten R., Markus T. NASA GSFC Current State of Sea Ice Cover Image Archive. Zenodo [internet]; 2025. Available at: https://earth.gsfc.nasa.gov/cryo/data/current-state-sea-ice-cover