References

For requests for pdfs of references cited in posts, please submit a request on the “Comments-tips” page. I’ll get back to you as soon as I can.

Download pdfs of select documents authored by me below:

Crockford, S.J. 2004. Animal Domestication and Vertebrate Speciation: A Paradigm for the Origin of Species. Ph.D. dissertation, University of Victoria (Canada), Interdisciplinary Studies. [filed at the National Library under Zoology].

Crockford, S.J. 2006. Rhythms of Life: Thyroid Hormone and the Origin of Species. Victoria: Trafford.

Crockford, S.J. 2012. Annotated Map of Ancient Polar Bear Remains of the World. Electronic resource available at http://polarbearscience/references/ ISBN 978-0-9917966-0-1.
DOWNLOAD HERE  Ancient Polar Bear Remains_Crockford 2012

Crockford, S.J. 2015. “The Arctic Fallacy: sea ice stability and the polar bear.” GWPF Briefing 16. The Global Warming Policy Foundation, London. Pdf here.

Crockford, S.J. 2017. Testing the hypothesis that routine sea ice coverage of 3-5 mkm2 results in a greater than 30% decline in population size of polar bears (Ursus maritimus). PeerJ Preprints 2 March 2017. Doi: 10.7287/peerj.preprints.2737v3 https://peerj.com/preprints/2737/

References by topic [updated when I can]

** Where polar bears live (and other basics)

Andersen, M. and Aars, J. 2016. Barents Sea polar bears (Ursus maritimus): population biology and anthropegenic threats. Polar Research 35:26029 http://www.polarresearch.net/index.php/polar/article/view/26029

Amstrup, S.C. 2003. Polar bear (Ursus maritimus). In Wild Mammals of North America, G.A. Feldhamer, B.C. Thompson and J.A. Chapman (eds), pg. 587-610. Johns Hopkins University Press, Baltimore.

Cronin, M.A., Amstrup, S.C., et al. 2009. Genetic variation, relatedness, and effective population size of polar bears (Ursus maritimus) in the southern Beaufort Sea, Alaska. Journal of Heredity 100: 681-690.

Derocher, A.E., Andersen, M., et al. 2010. Sexual dimorphism and the mating ecology of polar bears (Ursus maritimus) at Svalbard. Behavioral Ecology and Sociobiology 64: 939-946.

Derocher, A.E. & Lynch, W. 2012. Polar Bears: A Complete Guide to their Biology and Behavior. Johns Hopkins U. Press.

De Veer, Gerrit. 1609. The Three Voyages of William Barentsz to the Arctic Regions (English translation). Online. Pdf here.

Durner, G.M. & Amstrup, S.C. 1995. Movements of a polar bear from northern Alaska to northern Greenland. Arctic 48: 338-341.

Durner, G.M., Douglas, D.C., et al. 2006. A model for autumn pelagic distribution of female polar bears in the Chukchi Sea, 1987-1994. US Geological Survey. Reston, Virginia.

Crockford, S.J. 2012. Annotated Map of Ancient Polar Bear Remains of the World. Electronic resource available at https://polarbearscience/references ISBN 978-0-9917966-0-1. Pdf here.

Elliott, H.W. 1875. Polar bears on St. Matthew Island. Harper’s Weekly Journal of Civilization. May 1 issue. Harper and Brothers, New York.

Elliott, H.W. & Coues, E. 1875. A report upon the condition of affairs in the territory of Alaska. US Government Printing Office, Washington. http://tinyurl.com/a8zk6yk

Ogilvie, A.E.J., Barlow, L.K. et al. 2000. North Atlantic climate c. AD 1000: Millennial reflections on the Viking discoveries of Iceland, Greenland and North America. Weather 55: 34-45.

Lydersen, C. & Gjertz, I. 1986. Studies of the ringed seal (Phoca hispida Schreber 1775) in its breeding habitat in Kongsfjorden, Svalbard. Polar Research 4: 57-63.

Norwegian Polar Institute 2015. Polar bears in Svalbard in good condition – so far. Press release 23 December 2015. Available from http://www.npolar.no/en/news/2015/12-23-counting-of-polar-bears-in-svalbard.html

Norwegian Polar Institute 2016. Environmental monitoring of Svalbard and Jan Mayen: Polar bear (Ursus maritimus). Update of data, graphs, and results at 24 June 2016. http://www.mosj.no/en/fauna/marine/polar-bear.html

Packard, A.S. 1886. The former southern limits of the white or polar bear. American Naturalist 20(7): 655–659.

Peacock, E., Taylor, M.K., et al. 2013. Population ecology of polar bears in Davis Strait, Canada and Greenland. Journal of Wildlife Management 77: 463–476.

Ramsay, M.A. & Stirling, I. 1988. Reproductive biology and ecology of female polar bears (Ursus maritimus). Journal of Zoology London 214: 601-624.

Rausch, R.L. 1953. On the land mammals of St. Lawrence Island, Alaska. Murrelet 34: 18–26.

Rode, K.D., Regehr, E.V., et al. 2014. Variation in the response of an Arctic top predator experiencing habitat loss: feeding and reproductive ecology of two polar bear populations. Global Change Biology 20: 76-88.

Stirling, I. 2002. Polar bears and seals in the eastern Beaufort Sea and Amundsen Gulf: a synthesis of population trends and ecological relationships over three decades. Arctic 55 (Suppl. 1): 59-76.

Stirling, I. 2011. Polar Bears: The Natural History of a Threatened Species. Fitzhenry & Whiteside, Markham.

Stirling & Kiliaan. 1980. Population ecology studies of the polar bear in northern Labrador. Canadian Wildlife Service Occasional Paper 42.

Stirling et al. 1977. The ecology of the polar bear bears (Ursus maritimus) along the western coast of Hudson Bay. Canadian Wildlife Services Occasional Paper 33 http://parkscanadahistory.com/wildlife/paper-33.pdf

Smith, P., Stirling, I., et al. 1975. Notes on the present status of the polar bear (Ursus maritimus) in Ungava Bay and northern Labrador. Canadian Wildlife Service Progress Notes 53.

Van Meurs, R. & Splettstoesser, J.F. 2003. Farthest North Polar Bear (Letter to the Editor). Arctic 56: 309.

Wiig, Ø., Amstrup, S., et al. 2015. Ursus maritimus. The IUCN Red List of Threatened Species 2015: e.T22823A14871490. http://www.iucnredlist.org/details/22823/0

**Seasonal sea ice changes (and use by polar bears)

Arrigo, K.R. & van Dijken, G.L. 2015. Continued increases in Arctic Ocean primary production. Progress in Oceanography 136: 60–70.

Brown, Z.W., van Dijken, G.L. et al. 2011. A reassessment of primary production and environmental change in the Bering Sea. Journal of Geophysical Research 116: C08014. doi:10.1029/2010JC006766.

Cherry, S.G., Derocher, A.E., et al. 2013. Migration phenology and seasonal fidelity of an Arctic marine predator in relation to sea ice dynamics. Journal of Animal Ecology 82: 912-921.

Crockford, S.J. 2015. “The Arctic Fallacy: sea ice stability and the polar bear.” GWPF Briefing 16. The Global Warming Policy Foundation, London. Pdf here.

Derocher, A.E. 2005. Population ecology of polar bears at Svalbard, Norway. Population Ecology 47: 267-275

Derocher, A.E., Andersen, M., et al. 2010. Sexual dimorphism and the mating ecology of polar bears (Ursus maritimus) at Svalbard. Behavioral Ecology and Sociobiology 64: 939-946.

Derocher, A.E., Lunn, N.J., et al. 2004. Polar bears in a warming climate. Integrative and Comparative Biology 44: 163–176.

Frey, K.E., Moore, G.W.K., et al. 2015. Divergent patterns of recent sea ice cover across the Bering, Chukchi, and Beaufort seas of the Pacific Arctic Region. Progress in Oceanography 136: 32–49.

Furevik, T., Drange, H. et al. 2002. Anticipated changes in the Nordic Seas marine climate: Scenarios for 2020, 2050, and 2080. Fisken og Havet 2002-4: 1-13.

Gagnon, A.S. & Gough, W.A. 2005. Trends in the dates of ice freeze-up and breakup over Hudson Bay, Canada. Arctic 58: 370-382.

George, J.C., Druckenmiller, M.L., et al. 2015. Bowhead whale body condition and links to summer sea ice and upwelling in the Beaufort Sea. Progress in Oceanography 136: 250-262.

Harwood, L.A., Smith, T.G., George, J.C., Sandstrom, S.J., Walkusz, W. and Divoky, G.J. 2015. Change in the Beaufort Sea ecosystem: Diverging trends in body condition and/or production in five marine vertebrate species. Progress in Oceanography 136:263-273. http://www.sciencedirect.com/science/article/pii/S0079661115001007

Harwood, L.A., Smith, T.G., Melling, H., Alikamik, J. and Kingsley, M.C.S. 2012. Ringed seals and sea ice in Canada’s western Arctic: harvest-based monitoring 1992-2011. Arctic 65:377-390. http://arctic.synergiesprairies.ca/arctic/index.php/arctic/article/view/4236

Meier, W.N., Hovelsrud, G.K., et al. 2014. Arctic sea ice in transformation: A review of recent observed changes and impacts on biology and human activity. Reviews of Geophysics 52: 185-217.

Miles, M.W., Divine, D.V., et al. 2014. A signal of persistent Atlantic multidecadal variability in Arctic sea ice. Geophysical Research Letters 41: 463-469.

Moore, S.E. 2016. Is it ‘boom times’ for baleen whales in the Pacific Arctic region? Biology Letters 12:20160251. http://dx.doi.org/10.1098/rsbl.2016.0251 [open access]

National Snow and Ice Data Center (NSIDC). 2016. “Charctic” Interactive Sea Ice Graph. Available online.

Parkinson, C.L. 2014. Spatially mapped reductions in the length of the Arctic sea ice season. Geophysical Research Letters 41: 4316-4322.

Perovich, D., Meier, W., et al. 2015. Sea Ice. Arctic Report Card 2015, NOAA (eds M.O. Jeffries, et al.), pp. 33-40.

Schliebe, S., Rode, K.D., et al. 2008. Effects of sea ice extent and food availability on spatial and temporal distribution of polar bears during the fall open-water period in the southern Beaufort Sea. Polar Biology 31: 999-1010.

Scott, J.B. & Marshall, G.J. 2010. A step-change in the date of sea-ice breakup in western Hudson Bay. Arctic 63: 155-164.

Stern, H.L. and Laidre, K.L. 2016. Sea-ice indicators of polar bear habitat. Cryosphere 10: 2027-2041.

Stirling, I., Lunn, N.J., et al. 2004. Polar bear distribution and abundance on the southwestern Hudson Bay coast during open water season, in relation to population trends and annual ice patterns. Arctic 57: 15-26.

Stroeve, J., Holland, M.M., et al. 2007. Arctic sea ice decline: Faster than forecast. Geophysical Research Letters 34: L09501.

Stroeve, J., Markus, T, et al. 2014. Changes in Arctic melt season and implications for sea ice loss. Geophysical Research Letters 41: 1216-1224.

Vibe, C. 1965. The polar bear in Greenland. In, Proceedings of the 1st International Scientific Meeting on the Polar Bear. 6-10 Sept. 1965, IUCN Polar Bear Specialist Group. U. AK Internat. Conference Proc. Series, No. 1. Washington, pg. 17-25.

Vibe, C. 1967. Arctic animals in relation to climatic fluctuations. Meddelelser om Grønland. 170(5). C. A. Reitzels Forlag, Copenhagen.

Zhang, X. & Walsh, J.E. 2006. Toward a Seasonally Ice-Covered Arctic Ocean: Scenarios from the IPCC AR4 Model Simulations. Journal of Climate 19: 1730-1747.

**Counting polar bears

Andersen, M. and Aars, J. 2016. Barents Sea polar bears (Ursus maritimus): population biology and anthropegenic threats. Polar Research 35:26029 http://www.polarresearch.net/index.php/polar/article/view/26029

Bromaghin, J.F., McDonald, T.L., Stirling, I., Derocher, A.E., Richardson, E.S., Rehehr, E.V., Douglas, D.C., Durner, G.M., Atwood, T. and Amstrup, S.C. 2014 in press. Polar bear population dynamics in the southern Beaufort Sea during a period of sea ice decline. Ecological Applications http://www.esajournals.org/doi/abs/10.1890/14-1129.1 [paywalled]

Crockford, S.J. 2017. Testing the hypothesis that routine sea ice coverage of 3-5 mkm2 results in a greater than 30% decline in population size of polar bears (Ursus maritimus). PeerJ Preprints 2 March 2017. Doi: 10.7287/peerj.preprints.2737v3 https://peerj.com/preprints/2737/ [Open Access]

Dyck, M., Campbell, M., Lee, D., Boulanger, J. and Hedman, D. 2017. Aerial survey of the Western Hudson Bay polar bear sub-population 2016, final report (26 June 2017). Status report 2017-xx, Nunavut Department of Environment, Wildlife Research Section. Igloolik, Nunavut. pdf here.

Norwegian Polar Institute 2015. Polar bears in Svalbard in good condition – so far. Press release 23 December 2015. Available from http://www.npolar.no/en/news/2015/12-23-counting-of-polar-bears-in-svalbard.html

Norwegian Polar Institute 2016. Environmental monitoring of Svalbard and Jan Mayen: Polar bear (Ursus maritimus). Update of data, graphs, and results at 24 June 2016. http://www.mosj.no/en/fauna/marine/polar-bear.html

Obbard, M.E., Stapleton, S., Middel, K.R., Thibault, I., Brodeur, V., and Jutras, C. 2015. Estimating the abundance of the Southern Hudson Bay polar bear subpopulation with aerial surveys. Polar Biology 38:1713-1725. http://link.springer.com/article/10.1007/s00300-015-1737-5

Obbard, M.E., Cattet, M.R.I., Howe, E.J., Middel, K.R., Newton, E.J., Kolenosky, G.B., Abraham, K.F., and Greenwood, C.J. 2016. Trends in body condition in polar bears (Ursus maritimus) from the Southern Hudson Bay subpopulation in relation to changes in sea ice. Arctic Science 2:15-32. http://www.nrcresearchpress.com/doi/abs/10.1139/as-2015-0027#.V9d95DW72ds

Rode, K.D., Douglas, D., Durner, G., Derocher, A.E., Thiemann, G.W. and Budge, S. 2013. Comparison in polar bear response to sea ice loss in the Chukchi and southern Beaufort Seas. 28th Lowell Wakefield Fisheries Symposium, March 26–29. Anchorage, AK.

Rode, K.D., Regehr, E.V.,Douglas,D.,Durner, G.,Derocher, A.E., Thiemann, G.W. and Budge, S. 2014. Variation in the response of an Arctic top predator experiencing habitat loss: feeding and reproductive ecology of two polar bear populations. Global Change Biology 20:76–88. http://onlinelibrary.wiley.com/doi/10.1111/gcb.12339/abstract

SWG [Scientific Working Group to the Canada-Greenland Joint Commission on Polar Bear]. 2016. Re-Assessment of the Baffin Bay and Kane Basin Polar Bear Subpopulations: Final Report to the Canada-Greenland Joint Commission on Polar Bear. +636 pp. http://www.gov.nu.ca/documents-publications/349

Stapleton S., Atkinson, S., Hedman, D. & Garshelis, D. 2014. Revisiting Western Hudson Bay: using aerial surveys to update polar bear abundance in a sentinel population. Biological Conservation, 170, 38-47.

Stapleton, S., Peacock, E. & Garshelis, D. 2016. Aerial surveys suggest long-term stability in the seasonally ice-free Foxe Basin (Nunavut) polar bear population. Marine Mammal Science, 32, 181-201.

Wiig, Ø., Amstrup, S., et al. 2015. Ursus maritimus. The IUCN Red List of Threatened Species 2015: e.T22823A14871490. http://www.iucnredlist.org/details/22823/0

**Where females build maternity dens

Amstrup, S.C. 2003. Polar bear (Ursus maritimus). In Wild Mammals of North America, G.A. Feldhamer, B.C. Thompson and J.A. Chapman (eds), pg. 587-610. Johns Hopkins University Press, Baltimore.

Amstrup, S. & Gardner, C. 1994. Polar bear maternity denning in the Beaufort Sea. Journal of Wildlife Management 58: 1-10.

Bergen, S., Durner, G.M., et al. 2007. Predicting movements of female polar bears between summer sea ice foraging habitats and terrestrial denning habitats of Alaska in the 21st century: proposed methodology and pilot assessment. US Geological Survey. Reston, Virginia.

Derocher, A.E., Andersen, M., et al. 2011. Sea ice and polar bear den ecology at Hopen Island, Svalbard. Marine Ecology and Progress Series 441: 273-279.

Ferguson, S. H., Taylor, M. K., et al. 2000a. Influence of sea ice dynamics on habitat selection by polar bears. Ecology 81: 761-772.

Ferguson, S. H., Taylor, M. K., et al. 2000b. Relationships between denning of polar bears and conditions of sea ice. Journal of Mammalogy 81: 1118-1127.

Messier, F., Taylor, M.K. et al. 1994. Denning ecology of polar bears in the Canadian Arctic Archipelago. Journal of Mammalogy 75: 420-430.

Fischbach, A. S., Amstrup, S. C., et al. 2007. Landward and eastward shift of Alaskan polar bear denning associated with recent sea ice changes. Polar Biology 30: 1395-1405.

Lentfer, J. W. 1975. Polar bear denning on drifting sea ice. Journal of Mammalogy 56: 716-718.

Mauritzen, M., Derocher, A.E., et al. 2001. Space-use strategies of female polar bears in a dynamic sea ice habitat. Canadian Journal of Zoology 79: 1704-1713.

Olson, J.W., Rode, K.D., Eggett, D., Smith, T.S. and others. 2017. Collar temperature sensor data reveal long-term patterns in southern Beaufort Sea polar bear den distribution on pack ice and land. Marine Ecology Progress Series 564:211-224. https://doi.org/10.3354/meps12000

Olson, J.W. 2015. Maternal Denning Phenology and Substrate Selection of Polar Bears (Ursus maritimus) in the Southern Beaufort and Chukchi Seas. Masters Thesis, Brigham Young University.

Ovsyanikov, N.G. 2006. Research and conservation of polar bears on Wrangel Island. In Polar Bears: Proceedings of the 14th Working Meeting of the IUCN/SSC Polar Bear Specialist Group, 20-24 June 2005. Edited by Aars, J., et al. Occasional Paper of the IUCN Species Survival Commission 32. IUCN, Gland. pp. 167-171.

Ovsyanikov, N. 2010. Polar bear research on Wrangel Island and in the central Arctic Basin. In Polar Bears: Proceedings of the 15th meeting of the Polar Bear Specialists Group IUCN/SSC, 29 June-3 July 2009. Occasional Paper of the IUCN Species Survival Commission 43. Edited by Obbard, M.E., et al. IUCN Gland. pp. 171-178.

Scott, P.A. & Stirling, I. 2002. Chronology of terrestrial den use by polar bears in western Hudson Bay as indicated by tree growth anomalies. Arctic 55: 151-166.

Stirling, I. & Andriashek, D. 1992. Terrestrial maternity denning of polar bears in the eastern Beaufort Sea area. Arctic 45: 363-366.

Van de Velde (OMI), F., Stirling, I. et al. 2003. Polar bear (Ursus maritimus) denning in the area of the Simpson Peninsula, Nunavut. Arctic 56: 191-197.

Zeyl, E., Ehrich, D., et al. 2010. Denning-area fidelity and mitochondrial DNA diversity of female polar bears (Ursus maritimus) in the Barents Sea. Canadian Journal of Zoology 88: 1139-1148.

**Feasting/fasting way of life of polar bears

Amstrup, S.C. 2003. Polar bear (Ursus maritimus). In Wild Mammals of North America, G.A. Feldhamer, B.C. Thompson and J.A. Chapman (eds), pg. 587-610. Johns Hopkins University Press, Baltimore.

Cameron, M. F., Bengtson, J. L., et al. 2010. Status review of the bearded (Erignatha barbatus). NOAA Technical Memorandum NMFS-AFSC-211.

Department of Fisheries and Oceans Canada (DFO). 2014. Status of Northwest Atlantic harp seals, Pagophilus groenlandicus. Canadian Science Advisory Secretariat Science Advisory Report 2014/011.

Derocher, A.E. & Stirling, I. 1996. Aspects of survival in juvenile polar bears. Canadian Journal of Zoology 73: 1246–1252.

Derocher, A.E., Stirling, I. et al. 1992. Pregnancy rates and progesterone levels of polar bears in western Hudson Bay. Canadian Journal of Zoology 70: 561–566.

Derocher, A.E., Wiig, Ø., et al. 2002. Diet composition of polar bears in Svalbard and the western Barents Sea. Polar Biology 25: 448–452.

Hammill, M.O. & Smith T.G. 1991. The role of predation in the ecology of the ringed seal in Barrow Strait, Northwest Territories, Canada. Marine Mammal Science 7: 123–135.

Harwood, L.A., Smith, T.G., George, J.C., Sandstrom, S.J., Walkusz, W. and Divoky, G.J. 2015. Change in the Beaufort Sea ecosystem: Diverging trends in body condition and/or production in five marine vertebrate species. Progress in Oceanography 136:263-273. http://www.sciencedirect.com/science/article/pii/S0079661115001007

Harwood, L.A., Smith, T.G., Melling, H., Alikamik, J. and Kingsley, M.C.S. 2012. Ringed seals and sea ice in Canada’s western Arctic: harvest-based monitoring 1992-2011. Arctic 65:377-390. http://arctic.synergiesprairies.ca/arctic/index.php/arctic/article/view/4236

Ramsay, M.A. & Stirling, I. 1988. Reproductive biology and ecology of female polar bears (Ursus maritimus). Journal of Zoology London 214: 601-624. http://onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.1988.tb03762.x/abstract

Stirling, I. & Øritsland, N. A. 1995. Relationships between estimates of ringed seal (Phoca hispida) and polar bear (Ursus maritimus) populations in the Canadian Arctic. Canadian Journal of Fisheries and Aquatic Science 52: 2594 – 2612.

Thiemann, G.W., Iverson, S.J., et al. 2008. Polar bear diets and Arctic marine food webs: insights from fatty acid analysis. Ecological Monographs 78: 591-613.

Whiteman, J.P., Harlow, H.J., et al. 2015. Summer declines in activity and body temperature offer polar bears limited energy savings. Science 349: 295-298.

**Evolution

Barnes, I., Matheus, P., et al. 2002. Dynamics of Pleistocene population extinctions in Beringian brown bears. Science 295: 2267-2270.

Cahill JA, Green RE, et al. 2013. Genomic evidence for island population conversion resolves conflicting theories of polar bear evolution. PLoS Genetics 9(3): e1003345.

Crockford, S.J. 2004. Animal Domestication and Vertebrate Speciation: A Paradigm for the Origin of Species. Ph.D. dissertation, University of Victoria (Canada), Interdisciplinary Studies. [filed at the National Library under Zoology].

Crockford, S.J. 2006. Rhythms of Life: Thyroid Hormone and the Origin of Species. Victoria: Trafford.

Crockford, S.J. 2012a. Annotated Map of Ancient Polar Bear Remains of the World. Electronic resource available at https://polarbearscience/references ISBN 978-0-9917966-0-1.

Crockford, S.J. 2012b. Directionality in polar bear hybridization. Comment posted May 1 in response to Edwards et al. 2011. “Ancient hybridization and an Irish origin for the modern polar bear matriline.” Current Biology 21: 1251-1258.

Cronin, M.A., Amstrup, S.C. et al. 1991. Interspecific and intraspecific mitochondrial DNA variation in North American bears (Ursus). Canadian Journal of Zoology 69: 2985-2992.

Cronin, T. M. and Cronin, M.A. 2015. Biological response to climate change in the Arctic Ocean: the view from the past. Arktos 1:1-18 [Open access] http://link.springer.com/article/10.1007/s41063-015-0019-3

Cronin, M.A., Rincon, G., et al. 2014. Molecular phylogeny and SNP variation of polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus) derived from genome sequences. Journal of Heredity 105: 312-323.

Davison, J., Ho, S.Y.W., et al. 2011. Late-Quaternary biogeographic scenarios for the brown bear (Ursus arctos), a wild mammal model species. Quaternary Science Reviews 30: 418-430.

Edwards, C.J., Suchard, M.A., et al. 2011. Ancient hybridization and an Irish origin for the modern polar bear matriline. Current Biology 21: 1251-1258.

Derocher, A.E., Lunn, N.J. et al. 2004. Polar bears in a warming climate. Integrative and Comparative Biology 44: 163–176.

Hailer, F., Kutschera, V.E., et al. 2012. Nuclear genomic sequences reveal that polar bears are an old and distinct bear lineage. Science 336: 344-347.

Heaton, T.H., & Grady, F. 2003. The Late Wisconsin vertebrate history of Prince of Wales Island, Southeast Alaska. In Ice Age Cave Faunas of North America, Schubert, B.W., Mead, J.I., Graham, R.W. (eds.), pp.17-53. Indiana University Press, Bloomington.

Heaton, T.H. & Grady, F. 2009. The fossil bears of Southeast Alaska. Proceedings of the 15th International Congress of Speleology 1(1): I-N.

Heaton T.H., Talbot S.L. et al. 1996. An ice age refugium for large mammals in the Alexander Archipelago, southeastern Alaska. Quaternary Research 46: 189–192.

Krause, J., Unger, T., et al. 2008. Mitochondrial genomes reveal an explosive radiation of extinct and extant bears near the Miocene-Pliocene boundary. BMC Evolutionary Biology 8: 220.

Kurtén, B. 1968. Pleistocene Mammals of Europe. Weidenfeld and Nicolson, London.

Kurtén, B. & Anderson, E. 1980. Pleistocene Mammals of North America. Columbia University Press, New York.

Lindqvist, C., Schuster, S.C., et al. 2010. Complete mitochondrial genome of a Pleistocene jawbone unveils the origin of polar bear. Proceedings of the National Academy of Sciences USA 107: 5053-5057.

Liu, S., Lorenzen, E.D., et al.. 2014. Population genomics reveal recent speciation and rapid evolutionary adaptation in polar bears. Cell 157: 785-794.

Miller, W., Schuster, S.C., et al. 2012. Polar and brown bear genomes reveal ancient admixture and demographic footprints of past climate change. Proceedings of the National Academy of Sciences USA 109: E2382-E2390. doi: 10.1073/pnas.1210506109.

Paetkau, D., Amstrup, S.C., et al. 1999. Genetic structure of the world’s polar bear populations. Molecular Ecology 8: 1571–1584.

Pulquério, M. J. F. and R. A. Nichols. 2007. Dates from the molecular clock: how wrong can we be? Trends in Ecology and Evolution 22: 180-184.

Talbot, S.L. & Shields, G.F. 1996a. A phylogeny of the bears (Ursidae) inferred from complete sequences of three mitochondrial DNA genes. Molecular Phylogeny and Evolution 5: 567-575.

Talbot, S.L. & Shields, G.F., 1996b. Phylogeography of brown bears (Ursus arctos) of Alaska and paraphyly within the Ursidae. Molecular Phylogenetics and Evolution 5: 477-494.

**Last Glacial Maximum (& cold periods in geological history since)

Bradley, R.S. & England, J.H. 2008. The Younger Dryas and the sea of ancient ice. Quaternary Research 70: 1-10.

Caissie, B. E., Brigham-Grette, J., et al. 2010. Last Glacial Maximum to Holocene sea surface conditions at Umnak Plateau, Bering Sea, as inferred from diatom, alkenone, and stable isotope records. Paleoceanography 25: PA1206.

Clark, P. U., Dyke, A. S., et al. 2009. The Last Glacial Maximum. Science 325: 710-714.

Crockford, S. & Frederick, G. 2007. Sea ice expansion in the Bering Sea during the Neoglacial: evidence from archaeozoology. The Holocene 17: 699-706.

Crockford, S.J. & Frederick, G. 2011. Neoglacial sea ice and life history flexibility in ringed and fur seals. pg.65-91 in T. Braje et al. eds. Human Impacts on Seals, Sea Lions, and Sea Otters: Integrating Archaeology and Ecology in the Northeast Pacific. U. California Press, LA.

Crockford, S.J. 2008. Be careful what you ask for: archaeozoological evidence of mid-Holocene climate change in the Bering Sea and implications for the origins of Arctic Thule. Pp. 113-131 in G. Clark, et al. (eds.), Islands of Inquiry: Colonisation, Seafaring and the Archaeology of Maritime Landscapes. Terra Australis 29 ANU E Press, Canberra.

Dallimore, A., Enkin, et al. 2008. Postglacial evolution of a Pacific coastal fjord in British Columbia, Canada: interactions of sea-level change, crustal response, and environmental fluctuations — results from MONA core MD02-2494. Canadian Journal of Earth Science 45: 1345-1362.

De Vernal, A. & Hillaire-Marcel, C. 2000. Sea ice cover, sea-surface salinity and halo-/thermocline structure of the northwest North Atlantic: modern versus full glacial conditions. Quaternary Science Reviews 12: 65-85.

Gorbarenko, S. A., Khusid, T.A., et al. 2002. Glacial Holocene environment of the southeastern Okhotsk Sea: evidence from geochemical and palaeontological data. Palaeogeography, Palaeoclimatology, Palaeoecology 177: 237-263.

Hebbeln, D., Henrich, R. et al. 1998. Paleoceanography of the last interglacial/glacial cycle in the polar North Atlantic. Quaternary Science Reviews 17: 125-153.

Hetherington, R., Vaughn-Barrie, J., et al. 2004. Paleogeography, glacially induced crustal displacement, and Late Quaternary coastlines on the continental shelf of British Columbia, Canada. Quaternary Science Reviews 23: 295-318.

Katsuki, K. & Takahashi, K. 2005. Diatoms as paleoenvironmental proxies for seasonal productivity, sea-ice and surface circulation in the Bering Sea during the late Quaternary. Deep-Sea Research II 52: 2110-2130.

Kaufman, D.S. & Manley, W. F. 2004. Pleistocene maximum and Late Wisconsinan glacier extents across Alaska, USA. in J. Ehlers et al. (eds), Quaternary Glaciation-Extent and Chronology, Part II: North America, pg. 9-27. Elsevier, Amsterdam.

Mackie, Q., Fedje, D.W., et al. 2011. Early Environments and Archaeology of Coastal British Columbia. In N. F. Bicho, et al. (eds.), Trekking the Shore: Changing Coastlines and the Antiquity of Coastal Settlement, pp. 51–103. Interdisciplinary Contributions to Archaeology, Springer, New York.

Mann, D. H. & Hamilton, T. D. 1995. Late Pleistocene and Holocene paleoenvironments of the North Pacific coast. Quaternary Science Review 14: 449-471.

Mann, D. H. & Peteet, D. M. 1994. Extent and timing of the Last Glacial Maximum in southwestern Alaska. Quaternary Research 42: 136-148.

Stein, R., Fahl,K.,Schade, I. and others. 2017. Holocene variability in sea ice cover, primary production, and Pacific-Water inflow and climate change in the Chukchi and East Siberian Seas (Arctic Ocean). Journal of Quaternary Science 32(2):362-379.

Trend-Staid, M. & Prell, W. L. 2002. Sea surface temperature at the Last Glacial Maximum: A reconstruction using the modern analog technique. Paleoceanography 17: 1065.

**Interglacial & Holocene Optimum (warm periods in geological history)

Alley, R.B. 2000. The Younger Dryas cold interval as viewed from central Greenland. Quaternary Science Reviews 19: 213-226.

Atkinson, N. 2009. A 10400-year-old bowhead whale (Balaena mysticetus) skull from Ellef Ringnes Island, Nunavut: implications for sea-ice conditions in high Arctic Canada at the end of the last glaciation. Arctic 62: 38-44.

CAPE Last Interglacial Project Members, 2006. Last interglacial Arctic warmth confirms polar amplification of climate change. Quaternary Science Reviews 25: 1383-1400.

Condron, A. & Winsor, P. 2012. Meltwater routing and the Younger Dryas. Proceedings of the National Academy of Science USA. 109(49): 19928–19933.

Cutler, K.B., Edwards, R.L., et al. 2003. Rapid sea-level fall and deep-ocean temperature change since the last interglacial period. Earth and Planetary Science Letters 206: 253-271.

Dredge, L.A. 1992. Field Guide to the Churchill region, Manitoba: Glaciations, sea level changes, permafrost landforms, and archaeology of the Churchill and Gillam areas. Geological Survey of Canada Miscellaneous Report 53.

Dyke, A.S., & England, J.H. 2003. Canada’s most northerly postglacial bowhead whales (Balaena mysticetus): Holocene sea-ice conditions and polynya development. Arctic 56: 14-20.

Dyke, A. S., Hooper, J. et al. 1996. A history of sea ice in the Canadian Arctic Archipelago based on postglacial remains of bowhead whale (Balaena mysticetus). Arctic 49: 235-255.

Dyke, A.S., Hooper, J., et al. 1999. The late Wisconsinan and Holocene record of walrus (Odobenus rosmarus) from North America: a review with new data from arctic and Atlantic Canada. Arctic 52: 160-181.

Dyke, A.S., Savelle, J.M. et al. 2011. Paleoeskimo demography and Holocene sea-level history, Gulf of Boothia, Arctic Canada. Arctic 64: 151-168.

Lindqvist, C., Schuster, S.C., et al. 2010. Complete mitochondrial genome of a Pleistocene jawbone unveils the origin of polar bear. Proceedings of the National Academy of Sciences USA 107: 5053-5057.

Miller, W., Schuster, S.C., et al. 2012. Polar and brown bear genomes reveal ancient admixture and demographic footprints of past climate change. Proceedings of the National Academy of Sciences 109: E2382-E2390.

NIPCC 2014. Climate Change Reconsidered II: Biological Implications.

Nichols, H. 1967. Central Canadian palynology and its relevance to Northwestern Europe in the late Quaternary period. Review of Paleobotany and Palynology 2: 231-243.

Polyak, L., Alley, R.B., et al. 2010. History of sea ice in the Arctic. Quaternary Science Reviews 29: 1757-1778.

Stein, R., Fahl,K.,Schade, I. and others. 2017. Holocene variability in sea ice cover, primary production, and Pacific-Water inflow and climate change in the Chukchi and East Siberian Seas (Arctic Ocean). Journal of Quaternary Science 32(2):362-379.

Thomas, E.K., Briner, J.P. et a. 2016. A major increase in winter snowfall during the middle Holocene on western Greenland caused by reduced sea ice in Baffin Bay and the Labrador Sea. Geophysical Research Letters 43(10): 5302-5308.

 **The great slaughter of polar bears, 1880-1960

Honderich, J.E. 1991. Wildlife as a hazardous resource: an analysis of the historical interaction of humans and polar bears in the Canadian arctic. MA thesis, University of Waterloo, Ontario. [available via university interlibrary loan]

Scott, P.A. & Stirling, I. 2002. Chronology of terrestrial den use by polar bears in western Hudson Bay as indicated by tree growth anomalies. Arctic 55:151-166.

Stirling, I. 2011. Polar Bears: The Natural History of a Threatened Species. Fitzhenry & Whiteside, Markham.

**Arctic sea ice predictions

ACIA 2005. Arctic Climate Impact Assessment: Scientific Report. Cambridge University Press. Pdf here.

Amstrup, S.C., Marcot, B.G. et al. 2007. Forecasting the rangewide status of polar bears at selected times in the 21st century. US Geological Survey. Reston, Virginia. Pdf here.

Amstrup, S.C., Marcot, B.G. et al. 2008. A Bayesian network modeling approach to forecasting the 21st century worldwide status of polar bears. Arctic Sea Ice Decline: Observations, Projections, Mechanisms, and Implications (eds E.T. DeWeaver, C.M. Bitz & L.B. Tremblay), pp. 213–268. American Geophysical Union Monogr. Ser. No. 180, Washington, D.C. http://onlinelibrary.wiley.com/doi/10.1029/180GM14/summary and http://alaska.usgs.gov/science/biology/polar_bears/pubs.html

Crockford, S.J. 2017. Testing the hypothesis that routine sea ice coverage of 3-5 mkm2 results in a greater than 30% decline in population size of polar bears (Ursus maritimus). PeerJ Preprints 19 January 2017. Doi: 10.7287/peerj.preprints.2737v1 Open access. https://peerj.com/preprints/2737/

Douglas, D.C. 2010. Arctic Sea Ice Decline: Projected Changes in Timing and Extent of Sea Ice in the Bering and Chukchi Seas. Open-File Report 2010-1176. US Geological Survey. Reston, Virginia. Pdf here.

Durner, G.M., Douglas, D.C., et al. 2006. A model for autumn pelagic distribution of female polar bears in the Chukchi Sea, 1987-1994. US Geological Survey. Reston, Virginia. Pdf here.

Durner, G.M., Douglas, D.C., et al. 2007. Predicting 21st-century polar bear habitat distribution from global climate models. US Geological Survey. Reston, Virginia. Pdf here.

Durner, G.M., Douglas, D.C., et al. 2009. Predicting 21st-century polar bear habitat distribution from global climate models. Ecology Monographs 79: 25–58.

Furevik, T., Drange, H., et al. 2002. Anticipated changes in the Nordic Seas marine climate: Scenarios for 2020, 2050, and 2080. Fisken og Havet 2002-4: 1-13.

Hassol, S.J. 2004. Impacts of a Warming Arctic: Arctic Climate Impact Assessment Synthesis Report. Cambridge University Press, Cambridge UK. [summary for policy makers published ahead of the report containing the science background] Pdf here.

Hunter, C.M., Caswell, H., et al. 2007. Polar bears in the Southern Beaufort Sea II: Demography and population growth in relation to sea ice conditions. US Geological Survey. Reston. Pdf here.

Hunter et al. 2010. Pdf here.

IPCC 2007. Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge.

Overland, J.E. and Wang, M. 2013. When will the summer Arctic be nearly sea ice-free? Geophysical Research Letters 40: 2097–2101.

Wang, M. & Overland, J.E. 2015. Projected future duration of the sea-ice-free season in the Alaskan Arctic. Progress in Oceanography 136: 50-59.

** Polar bear population size predictions (future conservation status)

Amstrup, S.C., Marcot, B.G. et al. 2007. Forecasting the rangewide status of polar bears at selected times in the 21st century. US Geological Survey. Reston, VA. Pdf here

Amstrup, S.C., Marcot, B.G. et al. 2008. A Bayesian network modeling approach to forecasting the 21st century worldwide status of polar bears. Arctic Sea Ice Decline: Observations, Projections, Mechanisms, and Implications (eds E.T. DeWeaver, C.M. Bitz & L.B. Tremblay), pp. 213–268. American Geophysical Union Monogr. Ser. No. 180, Washington, DC. Pdf here.

Amstrup, S.C., DeWeaver, E.T., et al. 2010. Greenhouse gas mitigation can reduce sea-ice loss and increase polar bear persistence. Nature 468: 955–958.

Bergen, S., Durner, G.M., et al. 2007. Predicting movements of female polar bears between summer sea ice foraging habitats and terrestrial denning habitats of Alaska in the 21st century: proposed methodology and pilot assessment. US Geological Survey. Reston, VA. Pdf here.

Courtland, R. 2008. Polar bear numbers set to fall. Nature 453: 432-433.

Crockford, S.J. 2017. Testing the hypothesis that routine sea ice coverage of 3-5 mkm2 results in a greater than 30% decline in population size of polar bears (Ursus maritimus). PeerJ Preprints 19 January 2017. Doi: 10.7287/peerj.preprints.2737v3 Pdf here. Open access. https://peerj.com/preprints/2737/

Derocher, A.E., Aars, J., et al. 2013. Rapid ecosystem change and polar bear conservation. Conservation Letters 6:368-375.

Hunter, C.M., Caswell, H., et al. 2007. Polar bears in the southern Beaufort Sea II: demography and population growth in relation to sea ice conditions, 2001-2006. Administrative Report US Geological Survey, Reston, VA. Pdf here.

Kelly, B., Whiteley, A., et al. 2010. Comment: The Arctic melting pot. Nature 468: 891.

Obbard, M.E., McDonald, T.L., et al 2007. Polar bear population status in southern Hudson Bay, Canada. Administrative Report, U.S. Department of the Interior- U.S. Geological Survey, Reston, VA. Pdf here.

Post, E., Bhatt, U.S., et al. 2013. Ecological consequences of sea-ice decline. Science 341: 519-524.

Regehr, E.V., Hunter, C.M., et al. 2007a. Polar bears in the Southern Beaufort Sea I: Survival and breeding in relation to sea ice conditions. US Geological Survey. Reston, VA. Pdf here.

Regehr, E.V., Lunn, N.J., et al. 2007b. Effects of earlier sea ice breakup on survival and population size of polar bears in Western Hudson Bay. Journal of Wildlife Management 71: 2673-2683.

Rode, K. D., Amstrup, S.C. et al. 2007. Polar bears in the Southern Beaufort Sea III: Stature, mass, and cub recruitment in relationship to time and sea ice extent between 1982 and 2006. US Geological Survey. Reston, VA. Pdf here.

Stirling, I. & Derocher, A.E. 2012. Effects of climate warming on polar bears: a review of the evidence. Global Change Biology 18: 2694–2706.

Stirling, I. and Parkinson, C.L. 2006. Possible effects of climate warming on selected populations of polar bears (Ursus maritimus) in the Canadian Arctic. Arctic 59: 261–275.

Stirling, I., Lunn, N.J., et al. 1999. Long-term trends in the population ecology of polar bears in Western Hudson Bay in relation to climate change. Arctic 52: 294-306.

Stirling, I., Lunn, N.J., et al. 2004. Polar bear distribution and abundance on the southwestern Hudson Bay coast during open water season, in relation to population trends and annual ice patterns. Arctic 57: 15–26.

** Evidence for thriving and stable subpopulations

Atwood, T.C., Peacock, E., et al. 2016. Rapid environmental change drives increased land use by an Arctic marine predator. PLoS One 11(6): e0155932. doi:10.1371/journal.pone.0155932.

Berghund, N. 2015. Polar bears make a surprise comeback. Newsinenglish, December 24, 2015. Available from http://www.newsinenglish.no/2015/12/24/polar-bears-make-a-comeback/ [accessed May 22, 2016]

Castro de la Guardia, L., Myers, P.G. et a. 2017. Sea ice cycle in western Hudson Bay, Canada, from a polar bear perspective. Marine Ecology Progress Series in press. DOI 10.3354/meps11964.

Cherry, S.G., Derocher, A.E., et al. 2016. Habitat-mediated timing of migration in polar bears: an individual perspective. Ecology and Evolution in press. doi 10.1002/ece3.2233

Cherry, S.G., Derocher, A.E., et al. 2013. Migration phenology and seasonal fidelity of an Arctic marine predator in relation to sea ice dynamics. Journal of Animal Ecology 82: 912–921.

Crawford, J. & Quakenbush, L. 2013. Ringed seals and climate change: early predictions versus recent observations in Alaska. Presentation by Justin Crawfort, 28th Lowell Wakefield Fisheries Symposium, March 26–29, Anchorage, AK. Online. http://seagrant.uaf.edu/conferences/2013/wakefield-arctic-ecosystems/program.php.

Crawford, J.A., Quakenbush, L.T. et al. 2015. A comparison of ringed and bearded seal diet, condition and productivity between historical (1975–1984) and recent (2003–2012) periods in the Alaskan Bering and Chukchi seas. Progress in Oceanography 136: 133-150.

Crockford, S.J. 2017. Testing the hypothesis that routine sea ice coverage of 3-5 mkm2 results in a greater than 30% decline in population size of polar bears (Ursus maritimus). PeerJ Preprints 2 March 2017. Doi: 10.7287/peerj.preprints.2737v3 https://peerj.com/preprints/2737/

Cronin, M.A., Amstrup, S.C., et al. 2009. Genetic variation, relatedness, and effective population size of polar bears (Ursus maritimus) in the southern Beaufort Sea, Alaska. Journal of Heredity 100: 681-690.

Galicia, M.P., Thiemann, G.W., et al. 2016. Dietary habits of polar bears in Foxe Basin, Canada: possible evidence of a trophic regime shift mediated by a new top predator. Ecology and Evolution in press. doi: 10.1002/ece3.2173

Lunn, N.J., Servanty, S., et al. 2016. Demography of an apex predator at the edge of its range – impacts of changing sea ice on polar bears in Hudson Bay. Ecological Applications 26: 1302-1320.

Matishov, G.G., Chelintsev, N.G., et al. 2014. Assessment of the amount of polar bears (Ursus maritimus) on the basis of perennial vessel counts. Doklady Earth Sciences 458 (2):1312-1316.

Norwegian Polar Institute 2015. Polar bears in Svalbard in good condition – so far. Press release 23 December 2015. Available from http://www.npolar.no/en/news/2015/12-23-counting-of-polar-bears-in-svalbard.html [accessed July 1, 2016].

Obbard, M.E., Middel, K.R., et al. 2015. Estimating abundance of the Southern Hudson Bay polar bears subpopulation using aerial surveys. Polar Biology 38: 1713-1725.

Obbard, M.E., Cattet, M.R.I., et al. 2016. Trends in body condition in polar bears (Ursus maritimus) from the Southern Hudson Bay subpopulation in relation to changes in sea ice. Arctic Science 2: 15-32.

Peacock, E., Taylor, M.K., et al. 2013. Population ecology of polar bears in Davis Strait, Canada and Greenland. Journal of Wildlife Management 77: 463–476.

Pongracz, J.D. & Derocher, A.E. 2016. Summer refugia of polar bears (Ursus maritimus) in the southern Beaufort Sea. Polar Biology in press. doi 10.1007/s00300-016-1997-8

Rode, K. & Regehr, E.V. 2010. Polar bear research in the Chukchi and Bering Seas: A synopsis of 2010 field work. Unpublished report to the US Fish and Wildlife Service, Dept. Interior, Anchorage.

Rode, K.D., Peacock, E., et al. 2012. A tale of two polar bear populations: ice habitat, harvest and body condition. Population Ecology 54: 3–18.

Rode, K.D., Douglas, D., Durner, G., Derocher, A.E., Thiemann, G.W. and Budge, S. 2013. Comparison in polar bear response to sea ice loss in the Chukchi and southern Beaufort Seas. 28th Lowell Wakefield Fisheries Symposium, March 26–29. Anchorage, AK.

Rode, K.D., Regehr, E.V.,Douglas,D.,Durner, G.,Derocher, A.E., Thiemann, G.W. and Budge, S. 2014. Variation in the response of an Arctic top predator experiencing habitat loss: feeding and reproductive ecology of two polar bear populations. Global Change Biology 20:76–88. http://onlinelibrary.wiley.com/doi/10.1111/gcb.12339/abstract

Rode, K.D., Wilson, R.R., Regehr, E.V., St. Martin, M., Douglas, D.C., and Olson, J. 2015. Increased land use by Chukchi Sea polar bears in relation to changing sea ice conditions. PLoS One 10:e0142213. http://dx.doi.org/10.1371/journal.pone.0142213. Press release, USGS 11-12-2015

Rogers, M.C., Peacock, E., et al. 2015. Diet of female polar bears in the southern Beaufort Sea of Alaska: evidence for an emerging alternative foraging strategy in response to environmental change. Polar Biology 38: 1035-1047.

Sahanatien V. & Derocher A.E. 2012. Monitering sea ice habitat fragmentation for polar bear conservation. Animal Conservation 15: 397-406.

Stapleton S., Atkinson, S., et al. 2014. Revisiting Western Hudson Bay: using aerial surveys to update polar bear abundance in a sentinel population. Biological Conservation 170: 38-47.

Stapleton, S., Peacock, E. et al. 2016. Aerial surveys suggest long-term stability in the seasonally ice-free Foxe Basin (Nunavut) polar bear population. Marine Mammal Science 32: 181-201.

SWG [Scientific Working Group to the Canada-Greenland Joint Commission on Polar Bear. 2016. Re-Assessment of the Baffin Bay and Kane Basin Polar Bear Subpopulations: http://www.gov.nu.ca/documents-publications/349

Viengkone, M., Derocher, A.E., et al. 2016. Assessing polar bear (Ursus maritimus) population structure in the Hudson Bay region using SNPs. Ecology and Evolution in press. DOI:10.1002/ece3.2563.

Wilson, R.R., Regehr, E.V., et al. 2016. Invariant polar bear habitat selection during a period of sea ice loss. Proceedings of the Royal Society B 283: 20160380.

Whiteman, J.P., Harlow, H.J., et al. 2015. Summer declines in activity and body temperature offer polar bears limited energy savings. Science 349: 295-298.

York, J., Dowsley, M., et al. 2016. Demographic and traditional knowledge perspectives on the current status of Canadian polar bear subpopulations. Ecology and Evolution 6: 2897-2924.

**Evidence for thick ice development in the Beaufort Sea & Hudson Bay

Bromaghin, J.F., McDonald, T.L., et al. 2015. Polar bear population dynamics in the southern Beaufort Sea during a period of sea ice decline. Ecological Applications 25: 634-651.

Burns, J. J., Fay, F. H., et al. 1975. The relationships of marine mammal distributions, densities, and activities to sea ice conditions (Quarterly report 1975), pp. 77-78 in Environmental Assessment of the Alaskan Continental Shelf, Principal Investiagors’ Reports. July-September 1975, Volume 1. NOAA, Environmental Research Laboratories, Boulder Colorado. Pdf here.

Chambellant, M., Stirling, I., et al. 2012. Temporal variations in Hudson Bay ringed seal (Phoca hispida) life-history parameters in relation to environment. Journal of Mammalogy 93: 267-281.

Crockford, S.J. 2015. The Arctic Fallacy: Sea Ice Stability and the Polar Bear. GWPF Briefing 16. The Global Warming Policy Foundation, London.

Harwood, L.A., Smith, T.G. et al. 2000. Variation in reproduction and body condition of the ringed seal (Phoca hispida ) in western Prince Albert Sound, NT, Canada, as assessed through a harvest-based sampling program. Arctic 53: 422 – 431.

Harwood, L.A., Smith, T.G., et al. 2012. Ringed seals and sea ice in Canada’s western Arctic: harvest-based monitoring 1992–2011. Arctic 65: 377–390.

Harwood, L.A. and Stirling. I. 1992. Distribution of ringed seals in the southeastern Beaufort Sea during late summer. Canadian Journal of Zoology 70: 891-900.

Lentfer 1976. Polar bear management and research in Alaska 1974-76. Pg. 187-197 in [Anonymous]. Polar Bears: Proceedings of the 6th meeting of the Polar Bear Specialists Group IUCN/SSC, 7 December, 1976, Morges, Switzerland. Gland, Switzerland and Cambridge UK, IUCN.

Pilfold, N.W., Derocher, A.E., et al. 2014. Polar bear predatory behaviour reveals seascape distribution of ringed seal lairs. Population Ecology 56: 129-138.

Pilfold, N. W., Derocher, A. E., et al. 2015. Multi-temporal factors influence predation for polar bears in a changing climate. Oikos 124: 1098-1107.

Pilfold, N.W., McCall, A. et al. 2016. Migratory response of polar bears to sea ice loss: to swim or not to swim. Ecography 39 in press DOI: 10.1111/ecog.02109.

Stirling, I. 2002. Polar bears and seals in the eastern Beaufort Sea and Amundsen Gulf: a synthesis of population trends and ecological relationships over three decades. Arctic 55 (Suppl. 1): 59-76.

Stirling, I., Andriashek, D., et al. 1975a. Distribution and abundance of polar bears in the Eastern Beaufort Sea. Beaufort Sea Tech. Report #2, Dept. Environment, Victoria, B.C.

Stirling, I., Andriashek, D., et al. 1988. Assessment of the polar bear population in the eastern Beaufort Sea. Final Report to the Northern Oil and Gas Assessment Program. Canadian Wildlife Service, Edmonton, Alberta, Canada. 81 pp.

Stirling, I., Archibald, R. et al. 1975b. Distribution and abundance of seals in the Eastern Beaufort Sea. Beaufort Sea Tech. Report #1, Dept. Environment, Victoria, B.C.

Stirling, I. & Archibald, W.R. 1977. Aspects of predation of seals by polar bears. Journal of the Fisheries Board of Canada 34: 1126–1129.

Stirling, I, Cleator, H. et al. 1981. Marine mammals. In: Polynyas in the Canadian Arctic, Stirling, I. and Cleator, H. (eds), pg. 45-58. Canadian Wildlife Service Occasional Paper No. 45. Ottawa.

Stirling, I. & Derocher, A.E. 2012. Effects of climate warming on polar bears: a review of the evidence. Global Change Biology 18: 2694-2706.

Stirling, I, Kingsley, M. et al. 1982. The distribution and abundance of seals in the eastern Beaufort Sea, 1974–79. Canadian Wildlife Service Occasional Paper 47. Edmonton.

Stirling, I. & Lunn, N.J. 1997. Environmental fluctuations in arctic marine ecosystems as reflected by variability in reproduction of polar bears and ringed seals. In Ecology of Arctic Environments, Woodin, S.J. et al. (eds), pg. 167-181. Blackwell Science, UK.

Stirling, I., Schweinsburg, R.E., et al. 1980. Research on polar bears in Canada 1976-78. In Polar Bears: Proceedings of the 7th meeting of the Polar Bear Specialists Group IUCN/SSC, 30 Jan.-1 Feb. 1979. Eds. Anonymous. IUCN, Gland. pp. 45–53.

Stirling, I., Schweinsburg, R.E., et al. 1985. Research on polar bears in Canada 1978-80. Polar Bears: Proceedings of the 8th meeting of the Polar Bear Specialists Group IUCN/SSC, 15-19 Jan. 1981. (ed Anonymous), pp. 71-98. IUCN, Gland.

Stirling, I., Richardson, E., et al. 2008. Unusual predation attempts of polar bears on ringed seals in the southern Beaufort Sea: possible significance of changing spring ice conditions. Arctic 61: 14–22.

**Effects of thick spring ice on ringed seals & polar bears

Amstrup, S.C., Stirling, I., et al. 2006. Recent observations of intraspecific predation and cannibalism among polar bears in the Southern Beaufort Sea. Polar Biology 29: 997–1002.

Cherry, S.G., Derocher, A.E., et al. 2009. Fasting physiology of polar bears in relation to environmental change and breeding behavior in the Beaufort Sea. Polar Biology 32: 383-391

Crockford, S.J. 2015. The Arctic Fallacy: Sea Ice Stability and the Polar Bear. GWPF Briefing 16. The Global Warming Policy Foundation, London.

Harwood, L.A., Smith, T.G., et al. 2012. Ringed seals and sea ice in Canada’s western Arctic: harvest-based monitoring 1992-2011. Arctic 65: 377-390.

Pilfold, N.W., Derocher, A.E., et al. 2012. Age and sex composition of seals killed by polar bears in the eastern Beaufort Sea. PLoS ONE 7:e41429. Doi:10.1371/journal.pone.0041429.

Regehr, E.V., Hunter, C.M., et al. 2010. Survival and breeding of polar bears in the southern Beaufort Sea in relation to sea ice. Journal of Animal Ecology 79: 117–127.

Rode, K.D., Amstrup, S.C., et al. 2010. Reduced body size and cub recruitment in polar bears associated with sea ice decline. Ecological Applications 20: 768-782.

Rode, K.D., Douglas, D., et al. 2013. Comparison in polar bear response to sea ice loss in the Chukchi and southern Beaufort Seas. Oral presentation at the 28th Lowell Wakefield Fisheries Symposium, March 26-29. Anchorage, AK.

Rode, K. & Regehr, E.V. 2010. Polar bear research in the Chukchi and Bering Seas: A synopsis of 2010 field work. Unpublished report to the US Fish and Wildlife Service, Department of the Interior, Anchorage.

Rode, K.D., Regher, E.V. et al. 2014. Variation in the response of an Arctic top predator experiencing habitat loss: feeding and reproductive ecology of two polar bear populations. Global Change Biology 20: 76-88.

Smith, T.G. 1987. The Ringed Seal, Phoca hispida, of the Canadian Western Arctic. Canadian Bulletin of Fisheries and Aquatic Sciences 216. Department of Fisheries and Oceans, Ottawa.

Smith T.G. & Stirling I. 1975. The breeding habitat of the ringed seal (Phoca hispida), the birth lair and associated structures. Canadian Journal of Zoology 53: 1297-1305.

Stirling, I. 1997. The importance of polynyas, ice edges, and leads to marine mammals and birds. Journal of Marine Systems 10: 9-21.

Stirling, I. 2002. Polar bears and seals in the eastern Beaufort Sea and Amundsen Gulf: a synthesis of population trends and ecological relationships over three decades. Arctic 55 (Suppl. 1): 59-76.

Stirling, I., Andriashek, D., et al. 1975. Distribution and abundance of polar bears in the Eastern Beaufort Sea. Beaufort Sea Tech. Report #2, Dept. Environment, Victoria, B.C.

Stirling, I., Archibald, R. et al. 1975. Distribution and abundance of seals in the Eastern Beaufort Sea. Beaufort Sea Tech. Report #1, Dept. Environment, Victoria, B.C.

Stirling, I, Cleator, H. et al. 1981. Marine mammals. Polynyas in the Canadian Arctic (eds I. Stirling & H. Cleator), pp. 45-58. Canadian Wildlife Service Occasional Paper No. 45. Ottawa.

Stirling, I. and Derocher, A.E. 2013. Effects of climate warming on polar bears: a review of the evidence. Global Change Biology 18 (9): 2694-2706 doi:10.1111/j.1365-2486.2012.02753.x

Stirling, I. & Lunn, N.J. 1997. Environmental fluctuations in arctic marine ecosystems as reflected by variability in reproduction of polar bears and ringed seals. In Ecology of Arctic Environments, Woodin, S.J. and Marquiss, M. (eds), pg. 167-181. Blackwell Science, UK.

Stirling, I., Andriashek, D., et al. 1993. Habitat preferences of polar bears in the western Canadian Arctic in late winter and spring. Polar Record 29:13-24.

Stirling, I., McDonald, T.L., et al. 2011. Polar bear population status in the northern Beaufort Sea, Canada, 1971-2006. Ecological Applications 21: 859-876.

Stirling, I., Richardson, E., et al. 2008. Unusual predation attempts of polar bears on ringed seals in the southern Beaufort Sea: possible significance of changing spring ice conditions. Arctic 61: 14-22.

Stirling, I., Schweinsburg, R.E., et al. 1980. Proceedings of the 7th meeting of the Polar Bear Specialists Group IUCN/SSC, 30 January-1 February, 1979, Copenhagen, Denmark. Gland, Switzerland and Cambridge UK, IUCN., pg. 45-53.

**Effects of variable snow cover on ringed seals & polar bears

Calvert, W., Stirling, I., et al. 1986. Polar bear management in Canada 1982-84. In: Polar Bears: Proceedings of the 9th meeting of the Polar Bear Specialists Group IUCN/SSC, 9-11 Aug. 1985, Anonymous (eds). IUCN, Gland. Pg. 19-34.

Chambellant, M., Stirling, I., et al. 2012. Temporal variations in Hudson Bay ringed seal (Phoca hispida) life-history parameters in relation to environment. Journal of Mammalogy 93: 267-281.

Crockford, S.J. 2015. The Arctic Fallacy: Sea Ice Stability and the Polar Bear. GWPF Briefing 16. The Global Warming Policy Foundation, London.

Derocher, A.E. & Stirling, I. 1996. Aspects of survival in juvenile polar bears. Canadian Journal of Zoology 73: 1246-1252.

Ferguson, S.H., Stirling, I., et al. 2005. Climate change and ringed seal (Phoca hispida) recruitment in Western Hudson Bay. Marine Mammal Science 21: 121-135.

Hammill, M.O. & Smith T.G. 1991. The role of predation in the ecology of the ringed seal in Barrow Strait, Northwest Territories, Canada. Marine Mammal Science 7: 123–135.

Hezel, P.J., Zhang,X., et al. 2012. Projected decline in spring snow depth on Arctic sea ice caused by progressively later autumn open ocean freeze-up this century. Geophysical Research Letters 39: L17505, doi:10.1029/2012GL052794.

Holst, M., Stirling, I. et al. 1999. Age structure and reproductive rates of ringed seals (Phoca hispida) on the northwest coast of Hudson Bay in 1991 and 1992. Marine Mammal Science 15: 1357-1364.

Kwok, R., Panzer, B., et al. 2011. Airborne surveys of snow depth over Arctic sea ice. Journal of Geophysical Research 116: C11018, doi:10.1029/2011JC007371.

Lunn, N.J., Servanty, S., et al. 2016. Demography of an apex predator at the edge of its range – impacts of changing sea ice on polar bears in Hudson Bay. Ecological Applications 26: 1302-1320.

Martinez-Bakker, M.E., Sell, S.K., et al. 2013. Combined genetic and telemetry data reveal high rates of gene flow , migration, and long-distance dispersal potential in Arctic ringed seals (Pusa hispida). PLoS One 8: e77125.

Pilfold, N.W., Derocher, A.E., et al. 2014. Polar bear predatory behaviour reveals seascape distribution of ringed seal lairs. Population Ecology 56: 129-138.

Pilfold, N. W., Derocher, A. E., et al. 2015. Multi-temporal factors influence predation for polar bears in a changing climate. Oikos 124: 1098-1107.

Ramseier, R.O., Vant, M.R., et al. 1975. Distribution of the ice thickness in the Beaufort Sea. Beaufort Sea Technical Report #30. Canada Dept. of Environment, Victoria, B.C.

Ramsay, M.A. & Stirling, I. 1988. Reproductive biology and ecology of female polar bears (Ursus maritimus). Journal of Zoology London 214: 601-624.

Smith, T.G. & Stirling, I. 1975. The breeding habitat of the ringed seal (Phoca hispida): the birth lair and associated structures. Canadian Journal of Zoology 53: 1297-1305.

Stirling, I. & Derocher, A.E. 2012. Effects of climate warming on polar bears: a review of the evidence. Global Change Biology 18: 2694-2706.

Stirling, I., Lunn, N.J. et al. 1999. Long-term trends in the population ecology of polar bears in Western Hudson Bay in relation to climate change. Arctic 52: 294-306.

Stirling, I. & Parkinson, C.L. 2006. Possible effects of climate warming on selected populations of polar bears (Ursus maritimus) in the Canadian Arctic. Arctic 59: 261-275.

Stirling, I. & Smith, T.G. 2004. Implications of warm temperatures and an unusual rain event for the survival of ringed seals on the coast of southeastern Baffin Island. Arctic 57: 59–67.

Taylor, K.E., Stouffer, R.J. et al. 2012. An overview of CMIP5 and the experiment design. Bulletin of the American Meteorological Society 93: 485-498.

 **Conservation to 2006 (based on status at the time)

Anonymous. 1968. Proceedings of the First International Scientific Meeting on the Polar Bear, 6-10 Sept. 1965. University of Alaska International Conference Proceedings Series, No. 1.

Amstrup, S.C. & Wiig, O. (eds.) 1991. Polar Bears: Proceedings of the 10th meeting of the Polar Bear Specialists Group IUCN/SSC, 25-29 Oct. 1988. IUCN, Gland.

Belikov, S.E. 1995. Status of polar bear populations in the Russian Arctic 1993. Polar Bears: Proceedings of the 11th working meeting of the IUCN/SSC Polar Bear Specialists Group, 25-27 Jan. 1993. (eds Ø. Wiig, et al.), Occasional Paper of the IUCN Species Survival Commission, No. 10. IUCN, Gland. Pp. 115-119.

Larsen, T.S. & Stirling, I. 2009. The Agreement on the Conservation of Polar Bears – its History and Future. Norwegian Polar Institute Report 127, Tromso.

Lunn, N.J., Schliebe, S., et al. 2002. Polar Bears: Proceedings of the 13th working meeting of the IUCN/SSC Polar Bear Specialists Group, 23-28 June , 2001. Occasional Paper of the IUCN Species Survival Commission 26. IUCN, Gland.

**Conservation status based on predictions of future survival (after 2006)

Aars, J., Lunn, N. J. et al. 2006. Polar Bears: Proceedings of the 14th Working Meeting of the IUCN/SSC Polar Bear Specialist Group, 20-24 June 2005. Occasional Paper of the IUCN Species Survival Commission 32. IUCN, Gland.

Akçakaya, H.R., Butchart, S.H.M., et al 2006. Use and misuse of the IUCN Red List criteria in projecting climate change impacts on biodiversity. Global Change Biology 12: 2037–2043.

Amstrup, S.C. & Wiig, O. 1991. Polar Bears: Proceedings of the 10th meeting of the Polar Bear Specialists Group IUCN/SSC, 25-29 Oct. 1988. IUCN, Gland.

COSEWIC 2008. Assessment and Update Status Report on the Polar Bear Ursus maritimus in Canada. Committee on the Status of Endangered Wildlife in Canada.

Crockford, S.J. 2015. The Arctic Fallacy: Sea Ice Stability and the Polar Bear. GWPF Briefing 16. The Global Warming Policy Foundation, London.

Cronin, M.A. 2009. Are polar bears an endangered species? Range Magazine. Winter: 40-41.

Cronin, M.A., Amstrup, S.C., et al. 2009. Genetic variation, relatedness, and effective population size of polar bears (Ursus maritimus) in the southern Beaufort Sea, Alaska. Journal of Heredity 100: 681-690.

Derocher, A., Garner, G.W., et al. 1998. Polar Bears: Proceedings of the 12th meeting of the Polar Bear Specialists Group IUCN/SSC, 3-7 February 1997. IUCN, Gland.

Larsen, T.S. & Stirling, I. 2009. The Agreement on the Conservation of Polar Bears – its History and Future. Norwegian Polar Institute Report 127, Tromso.

Lowry, L. 2015. Odobenus rosmarus ssp. divergens. The IUCN Red List of Threatened Species 2015: e.T61963499A45228901.

Lowry, L. 2016. Pusa hispida. The IUCN Red List of Threatened Species 2016: e.T41672A45231341.

Lunn, N.J., Schliebe, S., et al. 2002. Polar Bears: Proceedings of the 13th working meeting of the IUCN/SSC Polar Bear Specialists Group, 23-28 June 2001. IUCN, Gland.

Marine Mammal Commission. 2007. The Marine Mammal Protection Act of 1972, as amended. Compiled and annotated for National Marine Fisheries Service, NOAA, Silver Spring, MD

Obbard, M.E., Theimann, G.W., et al. 2010. Polar Bears: Proceedings of the 15th meeting of the Polar Bear Specialists Group IUCN/SSC, 29 June-3 July 2009. IUCN Gland. http://pbsg.npolar.no/en/meetings/

Schliebe, S. Wiig, Ø., et al. 2006a. Ursus maritimus. The IUCN Red List of Threatened Species 2006. [see Wiig et al. 2007]

Schliebe, S. Evans, T., et al. 2006b. Range-wide status review of the polar bear (Ursus maritimus). Report prepared for the US Fish and Wildlife Service, Anchorage, Alaska.

SWG [Scientific Working Group to the Canada-Greenland Joint Commission on Polar Bear]. 2016. Re-Assessment of the Baffin Bay and Kane Basin Polar Bear Subpopulations: Final Report to the Canada-Greenland Joint Commission on Polar Bear. +636 pp. http://www.gov.nu.ca/documents-publications/349

Wiig, Ø., Born, E.W., et al. 1995. Polar Bears: Proceedings of the 11th working meeting of the IUCN/SSC Polar Bear Specialists Group, 25-27 January 199. IUCN, Gland.

Wiig, Ø., Aars, J., et al. 2007. Ursus maritimus. The IUCN Red List of Threatened Species 2007: e.T22823A9390963.

Wiig, Ø., Amstrup, S., et al. 2015. Ursus maritimus. The IUCN Red List of Threatened Species 2015: e.T22823A14871490. http://www.iucnredlist.org/details/22823/0

York, J., Dowsley, M., et al. 2016. Demographic and traditional knowledge perspectives on the current status of Canadian polar bear subpopulations. Ecology and Evolution 6: 2897-2924. DOI: 10.1002/ece3.2030

US Fish & Wildlife Service. 2008. Determination of threatened status for the polar bear (Ursus maritimus) throughout its range. Federal Register 73: 28212-28303.

Vongraven, D., Aars, J., et al.. 2012. A circumpolar monitoring framework for polar bears. Ursus 23 (sp2): 1-66.

**Polar bear conservation status (recent assessments)

Atwood, T.C., Marcot, B.G., et a. 2016. Forecasting the relative influence of environmental and anthropogenic stressors on polar bears. Ecosphere 7: e01370. 10.1002/ecs2.1370

Cronin, T. M. and Cronin, M.A. 2015. Biological response to climate change in the Arctic Ocean: the view from the past. Arktos 1:1-18 [Open access] http://link.springer.com/article/10.1007/s41063-015-0019-3

Crockford, S.J. 2015. “The Arctic Fallacy: sea ice stability and the polar bear.” GWPF Briefing 16. The Global Warming Policy Foundation, London. Pdf here.

Crockford, S.J. 2017. Testing the hypothesis that routine sea ice coverage of 3-5 mkm2 results in a greater than 30% decline in population size of polar bears (Ursus maritimus). PeerJ Preprints 2 March 2017. Doi: 10.7287/peerj.preprints.2737v3 https://peerj.com/preprints/2737/

Laidre K.L., Stern, H. et al. 2015. Arctic marine mammal population status, sea ice habitat loss, and conservation recommendations for the 21st century. Conservation Biology 29: 724–737.

Regehr, E.V., Laidre, K.L., et al. 2016. Conservation status of polar bears (Ursus maritimus) in relation to projected sea-ice declines. Biology Letters 12: 20160556.

US Fish & Wildlife Service (USFWS). 2011. 12-month finding on a petition to list the Pacific walrus as endangered or threatened. Federal Register 76: 7634–7676.

US Fish & Wildlife Service (USFWS). 2012a. Threatened status for the Arctic, Okhotsk and Baltic subspecies of the ringed seal. Federal Register 77: 76706–76738.

US Fish & Wildlife Service (USFWS). 2012b. Threatened status for the Beringia and Okhotsk distinct population segments of the Erignathus barbatus nauticus subspecies of the bearded seal. Federal Register 77: 76740–76768.