Ursus maritimus, Polar Bear IUCN Red List of Threatened Species™ ISSN 2307-8235 (online) IUCN...

The IUCN Red List of Threatened Species™ ISSN 2307-8235 (online) IUCN 2008: T22823A9391171

Ursus maritimus, Polar Bear

Assessment by: Schliebe, S., Wiig, Ø., Derocher, A. & Lunn, N. (IUCN SSC PolarBear Specialist Group)

View on www.iucnredlist.org

Citation: Schliebe, S., Wiig, Ø., Derocher, A. & Lunn, N. (IUCN SSC Polar Bear Specialist Group).2008. Ursus maritimus. The IUCN Red List of Threatened Species 2008: e.T22823A9391171.http://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T22823A9391171.en

Copyright: © 2015 International Union for Conservation of Nature and Natural Resources

Reproduction of this publication for educational or other non-commercial purposes is authorized without prior writtenpermission from the copyright holder provided the source is fully acknowledged.

Reproduction of this publication for resale, reposting or other commercial purposes is prohibited without prior writtenpermission from the copyright holder. For further details see Terms of Use.

The IUCN Red List of Threatened Species™ is produced and managed by the IUCN Global Species Programme, the IUCNSpecies Survival Commission (SSC) and The IUCN Red List Partnership. The IUCN Red List Partners are: BirdLifeInternational; Botanic Gardens Conservation International; Conservation International; Microsoft; NatureServe; RoyalBotanic Gardens, Kew; Sapienza University of Rome; Texas A&M University; Wildscreen; and Zoological Society of London.

If you see any errors or have any questions or suggestions on what is shown in this document, please provide us withfeedback so that we can correct or extend the information provided.

THE IUCN RED LIST OF THREATENED SPECIES™

http://www.iucnredlist.org/details/22823/0

http://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T22823A9391171.en

http://www.iucnredlist.org/info/terms-of-use

http://www.iucn.org/about/work/programmes/species/

http://www.iucn.org/about/work/programmes/species/who_we_are/about_the_species_survival_commission_/


http://www.iucnredlist.org/partners/partners

http://www.birdlife.org/


http://www.bgci.org/

http://www.conservation.org/

http://www.microsoft.com/

http://www.natureserve.org/

http://www.kew.org/

http://www.kew.org/

http://www.uniroma1.it/

http://www.tamu.edu/

http://www.wildscreen.org/

http://www.zsl.org/

mailto:[email protected]?Subject=IUCN Red List PDF - 10.2305/IUCN.UK.2008.RLTS.T22823A9391171.en&body=Please start your message below:%0D

Taxonomy

Kingdom Phylum Class Order Family

Animalia Chordata Mammalia Carnivora Ursidae

Taxon Name: Ursus maritimus Phipps, 1774

Synonym(s):

• Thalarctos maritimus

Regional Assessments:

• Europe

Common Name(s):

• English: Polar Bear• French: Ours blanc, Ours polaire• Spanish: Oso Polar

Taxonomic Source(s):

Wilson, D.E. 1976. Cranial variation in polar bears. International Conference on Bear Research and

Management 3: 447-453.

Taxonomic Notes:

Phipps (1774) first described polar bears as a distinct species and named it Ursus maritimus. Other

names were suggested including Thalassarctos, Thalarctos and Thalatarctos ultimately settling on Ursus

(Thalarctos) maritimus Erdbrink (1953) and Thenius (1953) based on interbreeding between brown

bears (Ursus arctos) and polar bears in zoos. Based on the fossil record and evolution Kurtén (1964)

recommended the Phipps (1774) name Ursus maritimus, which was promoted by Harrington (1966),

Manning (1971) and Wilson (1976) and is used today (see DeMaster and Stirling 1988, Wilson and

Reeder 1993, Amstrup 2003 for review and references).

Assessment Information

Red List Category & Criteria: Vulnerable A3c ver 3.1

Year Published: 2008

Date Assessed: June 30, 2008

Justification:

The assessment is based on a suspected population reduction of >30% within three generations (45

years) due to decline in area of occupancy (AOO), extent of occurrence (EOO) and habitat quality.

Polar bears rely almost entirely on the marine sea ice environment for their survival so that large scale

changes in their habitat will impact the population (Derocher et al. 2004). Global climate change posses

a substantial threat to the habitat of polar bears. Recent modeling of the trends for sea ice extent,

thickness and timing of coverage predicts dramatic reductions in sea ice coverage over the next 50-100

© The IUCN Red List of Threatened Species: Ursus maritimus – published in 2008.http://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T22823A9391171.en

1

http://www.iucnredlist.org/details/22823/1

http://www.iucnredlist.org/technical-documents/categories-and-criteria

years (Hassol 2004). Sea ice has declined considerably over the past half century. Additional declines of

roughly 10-50% of annual sea ice are predicted by 2100. The summer sea ice is projected to decrease by

50-100% during the same period. In addition the quality of the remaining ice will decline. This change

may also have a negative effect on the population size (Derocher et al. 2004). The effects of sea ice

change are likely to show large differences and variability by geographic location and periods of time,

although the long term trends clearly reveal substantial global reductions of the extent of ice coverage

in the Arctic and the annual time frames when ice is present.

While all bear species have shown adaptability in coping with their surroundings and environment, polar

bears are highly specialized for life in the Arctic marine environment. Polar bears exhibit low

reproductive rates with long generational spans. These factors make facultative adaptation by polar

bears to significantly reduced ice coverage scenarios unlikely. Polar bears did adapt to warmer climate

periods of the past. Due to their long generation time and the current greater speed of global warming,

it seems unlikely that polar bear will be able to adapt to the current warming trend in the Arctic. If

climatic trends continue polar bears may become extirpated from most of their range within 100 years.

There is little doubt that polar bears will have a lesser AOO, EOO and habitat quality in the future.

However, no direct relation exists between these measures and the abundance of polar bears. While

some have speculated that polar bears might become extinct within 100 years from now, which would

indicate a population decrease of >50% in 45 years based on a precautionary approach due to data

uncertainty. A more realistic evaluation of the risk involved in the assessment makes it fair to suspect

population reduction of >30%.

Other population stress factors that may also operate to impact recruitment or survival include toxic

contaminants, shipping, recreational viewing, oil and gas exploration and development. In addition to

this comes a potential risk of over-harvest due to increased quotas, excessive quotas or no quotas in

Canada and Greenland and poaching in Russia.

This assessment was reviewed by all the participants at the 14th Working Meeting of the IUCN SSC Polar

Bear Specialist Group held in Seattle, Washington, USA during June 20-24, 2005.

Previously Published Red List Assessments

2006 – Vulnerable (VU)

1996 – Lower Risk/conservation dependent (LR/cd)

1994 – Vulnerable (V)





1965 – Less rare but believed to be threatened-requires watching

Geographic Range


2

Range Description:

Polar bears live throughout the ice-covered waters of the circumpolar Arctic, and their range is limited

by the southern extent of sea ice. Although some occur in the permanent multi-year pack ice of the

central Arctic basin, they are most common in the annual ice over the continental shelf and inter-island

archipelagos that surround the polar basin. Polar bears that have continuous access to sea ice are able

to hunt throughout the year. However, in those areas where the sea ice melts completely each summer,

polar bears are forced to spend several months on land fasting on stored fat reserves until freeze-up.

Use of land by polar bears during the ice-free season appears to be increasing in certain locations.

The species is found in Canada (Manitoba, Newfoundland, Labrador, Nunavut, Northwest Territories,

Quebec, Yukon Territory, Ontario), Greenland/Denmark, Norway (including Svalbard), Russian

Federation (North European Russia, Siberia, Chukotka, Sakha (Yakutia), Krasnoyarsk), United States

(Alaska). Also, vagrants occasionally reach Iceland.

Country Occurrence:

Native: Canada (Labrador, Manitoba, Newfoundland I, Northwest Territories, Nunavut, Ontario, Québec,Yukon); Greenland; Norway; Russian Federation (Krasnoyarsk, North European Russia, West Siberia,Yakutiya); Svalbard and Jan Mayen; United States (Alaska)

FAO Marine Fishing Areas:

Native: Arctic Sea -


3

Distribution Map


4

PopulationThere are nineteen hypothesized subpopulations or stocks which number in total 20,000 to 25,000

bears. Considerable overlap of putative populations occurs and genetic differences among them are

small.

Current Population Trend: Decreasing

Habitat and Ecology (see Appendix for additional information)

Polar bears occur at low densities throughout their range and are most abundant in shallow water areas

near shore or where currents or upwellings increase biological productivity near ice areas associated

with open water, polynyas or lead systems. Polar bears are not as abundant in the high central arctic

over deeper waters of the polar basin.

Seasonally, in the summer open water season in the Canadian arctic islands and Svalbard, and in recent

years during the fall in northern Alaska and Russian Chukotka, polar bears may be found on land in

higher densities.

Breeding occurs in March to May, implantation is delayed until autumn, and birth is generally thought to

occur from late November to mid-January. Although some cubs are born in earth dens, most births

occur in snow dens that may be occupied between 5-6 months during the maternal event. In Alaska the

maternal dens are located on the offshore sea ice. Only pregnant female polar bears den for this

protracted period of time, during which time they rely on fat stores for energy and sustenance. The

average litter size is less than two. Cubs are dependent upon mothers until after the start of their third

year of life. Age of first reproduction is normally 5-6 years for females. These factors contribute to the

low reproductive potential for the species.

Systems: Terrestrial, Marine

Threats (see Appendix for additional information)

The Intergovernmental Panel on Climate Change and the Arctic Climate Impact Assessment have both

predicted that the Arctic is extremely vulnerable to projected climate change. Polar bears will likely be

shifted pole-ward if the sea ice retreats. According to new scenarios presented by the Nansen

Environmental and Remote Sensing Centre and others, the polar ice cap will disappear almost entirely

during summer in the next 100 years.

The increasing changes in the sea ice that affect access to prey will have a negative effect on the bears.

With less food, polar bears will fail to reproduce more often and give birth to smaller young that have

higher mortality rates.

Polar bears may be forced on shore for extended periods and rely on fat reserves deposited the previous

spring for survival. In such a situation they will be increasingly vulnerable to hunting if not regulated. If

these periods become excessively long, mortality will increase. Sea ice is also used for access to den

areas and if ice patterns change, existing den areas may be unreachable. Warmer temperatures and

higher winds may reduce ice thickness and increase ice drift. Because polar bears must walk against the

moving ice (like walking the wrong way on an escalator) increased ice movements will increase energy


5

use and reduce growth and reproduction.

Polar bears are the apex predator and are exposed to high levels of pollutants that are magnified with

each step higher in the food web. A key characteristic of the pollutants is that they tend to persist in the

environment and resist degradation. Many of the organochlorine pollutants are lipophilic or "fat loving"

and bond tightly to fat molecules. Polar bears are particularly vulnerable to organochlorines because

they eat a fat rich diet. Ringed, bearded, and harp seals comprise the main food of polar bears and the

blubber layer is preferentially eaten by the bears and subsequently, the intake of pollutants is high.

Certain areas of the Arctic, such as northeastern Greenland, the Barents Sea and the Kara Sea, have

higher levels of pollutants. Based on studies in other species, it is reasonable to believe that the

pollutant load of polar bears in some areas are negatively affecting the immune system, hormone

regulation, growth patterns, reproduction, and survival rates of polar bears. Recent studies have

suggested that the immune system is weaker in polar bears with higher levels of PCBs. A major concern

with polar bears pertains to their reproductive system. There are suggestions that species with delayed

implantation are more vulnerable to the effects of pollution through endocrine (hormone) disruption.

Further, female polar bears are food deprived during gestation their pollution loads increase because as

they use their fat stores, where pollutants are stored, for energy. Because the cubs are nursed on fat rich

milk, the cubs are exposed to very high pollution loads from their mother.

Oil development in the Arctic poses a wide range of threats to polar bears ranging from oil spills to

increased human-bear interactions. It is probable that an oil spill in sea ice habitat would result in oil

being concentrated in leads and between ice floes resulting in both polar bears and their main prey

(ringed and bearded seals) being directly exposed to oil. Another concern is that seals covered in oil may

be a major source of oil to polar bears. Other studies suggest that polar bears are sensitive to

disturbance at maternity den sites. Disturbance could occur both when a pregnant female is selecting a

den site and during the winter-spring after the cubs are born. If exploration or development occurred

sufficiently close to a den, the mother may abandon the den prematurely or abandon her offspring.

Over-harvest is an ongoing concern for some polar bear populations: particularly in areas where there is

no information on population size (e.g., Québec, east Greenland, and the Chukchi Sea) and no quotas. It

is important that population estimates and projections are based on substantiated scientific data. An

additional concern is that population inventory programs occur relatively infrequently in some areas so

if the harvest rate is above the sustainable level, the population may be reduced before the next

inventory is made. Recent development of co-management agreements and greater involvement of

local people and hunters is improving the management of polar bears in some areas.

Utilisation

The principle use of polar bears in the circumpolar arctic is for subsistence purposes. These include

consumption of meat; use of hides in the construction of clothing such as mittens, boots (mukluks), fur

ruffs for parkas, and fur pants; and small scale creation of items of handicraft. The US (Alaska), Canada

and Greenland manage a subsistence harvest. Norway and Russia prohibit harvest of polar bears. In

Russia during the early 1990s an unsanctioned harvest of polar bears began following dissolution of the

Soviet Union. Levels of harvest are not quantified.

In Canada a portion of the annual harvest is by sports hunters employing native guides utilizing


6

traditional harvest methods such as dog-teams. The harvest levels are regulated and based on principles

of sustainable resource management. Greenland introduced a quota system which came into force on

January 1, 2006 and plans to start sport hunting in the near future.

A small number of orphaned cubs are placed in zoos and public display facilities.

Research activities: live capture and release of polar bears.

Public viewing and photography are another form of utilization and occur locally at Churchill, Canada,

and other remote areas, at specific locals in Svalbard, Norway, and to a limited extent in location on the

north coast of Alaska.

Conservation Actions (see Appendix for additional information)

Conservation actions vary by jurisdiction. The International Agreement on the Conservation of Polar

Bears provides guidance, and Article II of the Agreement states that each contracting party "shall

manage polar bear populations in accordance with sound conservation practices based on the best

available scientific information," and according to Article VII, "The Contracting Parties shall conduct

national research programs on polar bears" and "..consult with each other on the management of

migrating polar bear populations". These articles have been important for stimulating governments to

support applied research to answer management questions regarding polar bears throughout their

range. This work is coordinated through the IUCN SSC Polar Bear Specialist Group (PBSG). Resolutions

from the PBSG are developed and directed toward ensuring that the terms and intentions of the

Agreement are being met.

Coordinated research is ongoing, management actions reviewed for consistency, and legislation to effect

bilateral management for internationally shared populations such as between the US-Russia is being

pursued. Additional cooperative management agreements between Canada and Greenland are

desirable and currently being developed.

Additional details of the Global Status and Management of Polar Bears are contained in the IUCN

"Status Survey and Conservation Action Plan: Bears" (Servheen et al. 1999).

It is listed on CITES Appendix II.

Credits

Assessor(s): Schliebe, S., Wiig, Ø., Derocher, A. & Lunn, N. (IUCN SSC Polar Bear SpecialistGroup)

Reviewer(s): Derocher, A.E. & Born, E.W. (Polar Bear Red List Authority)


7

BibliographyAmstrup, S. C. 2003. Polar bear, Ursus maritimus. In: G. A. Feldhamer, B. C. Thomson and J. A. Chapman(eds), Wild Mammals of North America: Biology, Management, and Conservation, pp. 587–610. JohnHopkins University Press, Baltimore, MD, USA.

DeMaster, D. and Stirling, I. 1981. Ursus maritimus. Mammalian Species 145: 1-7.

Derocher, A. E., Lunn, N. J. and Stirling, I. 2004. Polar bears in a warming climate. IntegratedComparative Biology 44: 163–176.

Groombridge, B. (ed.). 1994. IUCN Red List of Threatened Animals. IUCN, Gland, Switzerland andCambridge, UK.

Hassol, S. J. 2004. Impacts of a Warming Arctic. Cambridge University Press, Cambridge, UK.

IUCN. 1990. IUCN Red List of Threatened Animals. IUCN, Gland, Switzerland and Cambridge, UK.

IUCN. 2008. 2008 IUCN Red List of Threatened Species. Available at: http://www.iucnredlist.org.(Accessed: 5 October 2008).

IUCN Conservation Monitoring Centre. 1986. 1986 IUCN Red List of Threatened Animals. IUCN, Gland,Switzerland and Cambridge, UK.

IUCN Conservation Monitoring Centre. 1988. IUCN Red List of Threatened Animals. IUCN, Gland,Switzerland and Cambridge, UK.

Lunn, N. J., Schliebe, S. and Born, E. W. 2002. Polar Bears. Proceedings of the 13th Working Meeting ofthe IUCN/SSC Polar Bear Specialist Group.. Nuuk, Greenland.

Manning, T. H. 1971. Geographical variation in the polar bear Ursus maritimus Phipps. Canadian WildlifeService, Ottawa, Canada.

Polar Bear Specialist Group. 2004. Specialist Group website. Available at: http://pbsg.npolar.no/.

Rosing-Asvid, A., Born, E. W. and Kingsley, M. 2003. Age at sexual maturity of males and timing of matingseason of polar bears (Ursus maritimus) in Greenland. Polar Biology 25: 878–883.

Scott, P. 1965. Section XIII. Preliminary List of Rare Mammals and Birds. The Launching of a New Ark.First Report of the President and Trustees of the World Wildlife Fund. An International Foundation forsaving the world's wildlife and wild places 1961-1964, pp. 15-207. Collins, London, UK.

Servheen, C., Herrero, S. and Peyton, B. 1998. Bears. Status Survey and Conservation Action Plan.IUCN/SSC Bear and Polar Bear Specialist Groups, Gland, Switzerland and Cambridge, UK.

Thornback, J. and Jenkins, M. 1982. The IUCN Mammal Red Data Book. Part 1: Threatened mammaliantaxa of the Americas and the Australasian zoogeographic region (excluding Cetacea). IUCN, Gland,Switzerland.

Wozencraft, W.C. 1993. Order Carnivora. In: D.E. Wilson and D.M. Reeder (eds), Mammal Species of theWorld: A Taxonomic and Geographic Reference. Second Edition, pp. 279-344. Smithsonian InstitutionPress, Washington, DC, USA.

Wozencraft, W.C. 2005. Order Carnivora. In: D.E. Wilson and D.M. Reeder (eds), Mammal Species of theWorld: A Taxonomic and Geographic Reference. Third Edition, pp. 532-628. Smithsonian InstitutionPress, Washington, DC, USA.


8

http://www.iucnredlist.org

http://pbsg.npolar.no/

CitationSchliebe, S., Wiig, Ø., Derocher, A. & Lunn, N. (IUCN SSC Polar Bear Specialist Group). 2008. Ursusmaritimus. The IUCN Red List of Threatened Species 2008: e.T22823A9391171.http://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T22823A9391171.en

DisclaimerTo make use of this information, please check the Terms of Use.

External ResourcesFor Images and External Links to Additional Information, please see the Red List website.


9

http://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T22823A9391171.en

http://www.iucnredlist.org/info/terms-of-use

http://www.iucnredlist.org/details/links/22823/0

Appendix

Habitats(http://www.iucnredlist.org/technical-documents/classification-schemes)

Habitat Season SuitabilityMajorImportance?

3. Shrubland -> 3.1. Shrubland - Subarctic - Marginal -

9. Marine Neritic -> 9.10. Marine Neritic - Estuaries - Suitable -

10. Marine Oceanic -> 10.1. Marine Oceanic - Epipelagic (0-200m) - Suitable -

Threats(http://www.iucnredlist.org/technical-documents/classification-schemes)

Threat Timing Scope Severity Impact Score

1. Residential & commercial development -> 1.2.Commercial & industrial areas

Ongoing - - -

Stresses: 1. Ecosystem stresses -> 1.1. Ecosystem conversion

1. Ecosystem stresses -> 1.2. Ecosystem degradation

3. Energy production & mining -> 3.2. Mining &quarrying

Ongoing - - -



4. Transportation & service corridors -> 4.3. Shippinglanes

Future - - -



2. Species Stresses -> 2.2. Species disturbance

5. Biological resource use -> 5.1. Hunting & trappingterrestrial animals -> 5.1.1. Intentional use (species isthe target)

Ongoing - - -

Stresses: 2. Species Stresses -> 2.1. Species mortality

5. Biological resource use -> 5.1. Hunting & trappingterrestrial animals -> 5.1.2. Unintentional effects(species is not the target)

Ongoing - - -


6. Human intrusions & disturbance -> 6.1.Recreational activities

Ongoing - - -

Stresses: 2. Species Stresses -> 2.2. Species disturbance

6. Human intrusions & disturbance -> 6.3. Work &other activities

Ongoing - - -

Stresses: 2. Species Stresses -> 2.2. Species disturbance

7. Natural system modifications -> 7.2. Dams & watermanagement/use -> 7.2.11. Dams (size unknown)

Future - - -



10

http://www.iucnredlist.org/technical-documents/classification-schemes



9. Pollution -> 9.2. Industrial & military effluents ->9.2.1. Oil spills

Ongoing - - -


9. Pollution -> 9.2. Industrial & military effluents ->9.2.3. Type Unknown/Unrecorded

Ongoing - - -

Stresses: 1. Ecosystem stresses -> 1.2. Ecosystem degradation

11. Climate change & severe weather -> 11.1. Habitatshifting & alteration

Ongoing - - -



2. Species Stresses -> 2.2. Species disturbance

2. Species Stresses -> 2.3. Indirect species effects ->2.3.7. Reduced reproductive success

2. Species Stresses -> 2.3. Indirect species effects ->2.3.8. Other

Conservation Actions in Place(http://www.iucnredlist.org/technical-documents/classification-schemes)

Conservation Actions in Place

In-Place Land/Water Protection and Management

Occur in at least one PA: Yes

In-Place Education

Included in international legislation: Yes

Subject to any international management/trade controls: Yes

Conservation Actions Needed(http://www.iucnredlist.org/technical-documents/classification-schemes)

Conservation Actions Needed

1. Land/water protection -> 1.1. Site/area protection

1. Land/water protection -> 1.2. Resource & habitat protection

2. Land/water management -> 2.1. Site/area management

5. Law & policy -> 5.1. Legislation -> 5.1.1. International level

5. Law & policy -> 5.1. Legislation -> 5.1.2. National level

5. Law & policy -> 5.1. Legislation -> 5.1.3. Sub-national level

5. Law & policy -> 5.4. Compliance and enforcement -> 5.4.1. International level

5. Law & policy -> 5.4. Compliance and enforcement -> 5.4.2. National level

5. Law & policy -> 5.4. Compliance and enforcement -> 5.4.3. Sub-national level


11



Research Needed(http://www.iucnredlist.org/technical-documents/classification-schemes)

Research Needed

1. Research -> 1.2. Population size, distribution & trends

1. Research -> 1.3. Life history & ecology

1. Research -> 1.5. Threats

1. Research -> 1.6. Actions

3. Monitoring -> 3.1. Population trends

0. Root -> 4. Other

Additional Data Fields

Population

Population severely fragmented: No


12


The IUCN Red List of Threatened Species™ ISSN 2307-8235 (online) IUCN 2008: T22823A9391171

The IUCN Red List Partnership

The IUCN Red List of Threatened Species™ is produced and managed by the IUCN Global Species

Programme, the IUCN Species Survival Commission (SSC) and The IUCN Red List Partnership. The IUCN

Red List Partners are: BirdLife International; Botanic Gardens Conservation International; Conservation

International; Microsoft; NatureServe; Royal Botanic Gardens, Kew; Sapienza University of Rome; Texas

A&M University; Wildscreen; and Zoological Society of London.

THE IUCN RED LIST OF THREATENED SPECIES™


13




http://www.iucnredlist.org/partners/partners


http://www.bgci.org/



http://www.microsoft.com/

http://www.natureserve.org/

http://www.kew.org/

http://www.uniroma1.it/



http://www.wildscreen.org/

http://www.zsl.org/

Date post:	27-Jun-2018
Category:	Documents
Upload:	vuque
View:	217 times
Download:	0 times

Ursus maritimus, Polar Bear IUCN Red List of Threatened Species™ ISSN 2307-8235 (online) IUCN...

Documents