Geographic variation of PCB congeners in polar bears (Ursus maritimus) from Svalbard east to the Chukchi Sea

Polar Biology ◽  
2001 ◽  
Vol 24 (4) ◽  
pp. 231-238 ◽  
Author(s):  
M. Andersen ◽  
E. Lie ◽  
A.E. Derocher ◽  
S.E. Belikov ◽  
A. Bernhoft ◽  
...  
Keyword(s):  
Geographic Variation ◽  
Chukchi Sea ◽  
Ursus Maritimus ◽  
Polar Bears ◽  
Pcb Congeners

scholarly journals Polar Bear (Ursus maritimus) Behavior near Icebreaker Operations in the Chukchi Sea, 1991

ARCTIC ◽  
2016 ◽  
Vol 69 (2) ◽  
Author(s):  
Mari A. Smultea ◽  
Jay Brueggeman ◽  
Frances Robertson ◽  
Dagmar Fertl ◽  
Cathy Bacon ◽  
...  
Keyword(s):  
Climate Change ◽  
Human Activity ◽  
Polar Bear ◽  
Chukchi Sea ◽  
Group Behavior ◽  
Ursus Maritimus ◽  
The Arctic ◽  
Polar Bears ◽  
Running Away ◽  
Significant Difference

Increasing interactions of polar bears (Ursus maritimus) with human activity, combined with impacts of climate change, are of critical concern for the conservation of the species. Our study quantifies and describes initial reactions and behaviors of polar bears observed from an icebreaker during summer 1991 at two exploratory drilling sites (near sites drilled in 2015) located in the Chukchi Sea 175 km and 312 km west of Barrow, Alaska. Polar bear behavior was described using continuous sampling of six predetermined focal group behavior states (walking, running, swimming, resting, feeding or foraging, unknown) and six behavioral reaction events (no reaction, walking away, running away, approaching, vigilance [i.e., watching], unknown). Forty-six bears in 34 groups were monitored from the Robert LeMeur (an Arctic Class 3 icebreaker) for periods of five minutes to 16.1 hours. Significantly more bear groups reacted to icebreaker presence (79%) than not (21%), but no relationship was found between their reactions and distance to or activity of the icebreaker. Reactions were generally brief; vigilance was the most commonly observed reaction, followed by walking or running away for short (< 5 minutes) periods and distances (< 500 m). Eleven percent of bear groups approached the vessel. No significant difference was found between reactions when cubs were present and those when cubs were absent. Despite the limited sample sizes, these findings are relevant to assessing potential impacts of resource development and shipping activities on polar bears, especially given the sparsity of such information in the face of growing human activity in the Arctic offshore areas. Overall, climate change is leading to longer and more extensive open-water seasons in the Arctic and therefore to increasing marine traffic—more vessels (including icebreakers) for a longer time each year over a wider area. 

Microsatellite DNA and mitochondrial DNA variation in polar bears (Ursus maritimus) from the Beaufort and Chukchi seas, Alaska

2006 ◽  
Vol 84 (5) ◽  
pp. 655-660 ◽  
Author(s):  
M.A. Cronin ◽  
S.C. Amstrup ◽  
K.T. Scribner
Keyword(s):  
Mitochondrial Dna ◽  
Microsatellite Dna ◽  
Chukchi Sea ◽  
Genetic Data ◽  
Beaufort Sea ◽  
Ursus Maritimus ◽  
Polar Bears ◽  
Dna Variation ◽  
Movement Data ◽  
Mtdna Haplotype

Radiotelemetry data have shown that polar bears ( Ursus maritimus Phipps, 1774 ) occur in separate subpopulations in the Chukchi Sea and the southern Beaufort Sea. However, segregation is not absolute, and there is overlap of ranges of animals in each subpopulation. We used genetic variation at eight microsatellite DNA loci and mitochondrial DNA (mtDNA) to further assess the degree of spatial structure of polar bears from the Chukchi and southern Beaufort seas. Microsatellite allele frequencies and mtDNA haplotype frequencies of bears from the southern Beaufort and Chukchi seas did not differ significantly. Lack of differentiation at both maternally inherited mtDNA and bi-parentally inherited microsatellite loci suggests that gene flow between the two areas is mediated by both sexes. The genetic data indicate that polar bears in the southern Beaufort and Chukchi seas compose one interbreeding population. However, there is considerable fidelity to ranges in each area, particularly by adult females. The combined genetic and movement data suggest that polar bears could be managed as Beaufort Sea and Chukchi Sea subpopulations of a combined southern Beaufort Sea and Chukchi Sea population.

Geographic variation in growth of polar bears (Ursus maritimus)

1998 ◽  
Vol 245 (1) ◽  
pp. 65-72 ◽  
Author(s):  
A. E. Derocher ◽  
I. Stirling
Keyword(s):  
Geographic Variation ◽  
Ursus Maritimus ◽  
Polar Bears

Relationships Between Plasma Levels of Organochlorines, Retinol and Thyroid Hormones from Polar Bears (Ursus maritimus) at Svalbard

2001 ◽  
Vol 62 (4) ◽  
pp. 227-241 ◽  
Author(s):  
Janneche Utne Skaare ◽  
Aksel Bernhoft ◽  
Øystein Wiig ◽  
Kaare R. Norum ◽  
Egil Haug ◽  
...  
Keyword(s):  
Thyroid Hormones ◽  
Plasma Levels ◽  
Ursus Maritimus ◽  
Polar Bears

Performance of helicopter-based biopsy darting of polar bears (Ursus maritimus) on the spring sea ice

2021 ◽  
Vol 67 (6) ◽  
Author(s):  
Thomas S. Jung ◽  
Michael J. Suitor ◽  
Steve Baryluk
Keyword(s):  
Sea Ice ◽  
Ursus Maritimus ◽  
Polar Bears ◽  
Spring Sea Ice

New insights into dietary management of polar bears ( Ursus maritimus ) and brown bears ( U. arctos )

Zoo Biology ◽  
2021 ◽  
Author(s):  
Charles T. Robbins ◽  
Troy N. Tollefson ◽  
Karyn D. Rode ◽  
Joy A. Erlenbach ◽  
Amanda J. Ardente
Keyword(s):  
Ursus Maritimus ◽  
Dietary Management ◽  
Polar Bears ◽  
Brown Bears

scholarly journals Polar bears (Ursus maritimus) mating during late June on the pack ice of northern Svalbard, Norway

2015 ◽  
Vol 34 (1) ◽  
pp. 25786 ◽  
Author(s):  
Thomas G. Smith ◽  
Jon Aars
Keyword(s):  
Ursus Maritimus ◽  
Polar Bears ◽  
Pack Ice

scholarly journals Three decades (1983–2010) of contaminant trends in East Greenland polar bears (Ursus maritimus). Part 2: Brominated flame retardants

2013 ◽  
Vol 59 ◽  
pp. 494-500 ◽  
Author(s):  
Rune Dietz ◽  
Frank F. Rigét ◽  
Christian Sonne ◽  
Erik W. Born ◽  
Thea Bechshøft ◽  
...  
Keyword(s):  
Flame Retardants ◽  
Brominated Flame Retardants ◽  
Ursus Maritimus ◽  
Polar Bears ◽  
East Greenland

scholarly journals Integrated Population Modeling Provides the First Empirical Estimates of Vital Rates and Abundance for Polar Bears in the Chukchi Sea

2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Eric V. Regehr ◽  
Nathan J. Hostetter ◽  
Ryan R. Wilson ◽  
Karyn D. Rode ◽  
Michelle St. Martin ◽  
...  
Keyword(s):  
Chukchi Sea ◽  
Population Modeling ◽  
Polar Bears ◽  
Vital Rates ◽  
Empirical Estimates

The breeding habitat of the ringed seal (Phoca hispida). The birth lair and associated structures

1975 ◽  
Vol 53 (9) ◽  
pp. 1297-1305 ◽  
Author(s):  
Thomas G. Smith ◽  
Ian Stirling
Keyword(s):  
Ursus Maritimus ◽  
Ringed Seal ◽  
Breeding Habitat ◽  
Polar Bears ◽  
Alopex Lagopus ◽  
Phoca Hispida ◽  
Arctic Foxes ◽  
Different Types ◽  
Amundsen Gulf

The subnivean lairs of the ringed seal (Phoca hispida) were studied in the Amundsen Gulf and Prince Albert Sound areas from 1971 through 1974. The structure of several different types of lairs are described. The existence of a birth-lair complex consisting of several closely adjacent lairs appears likely. The spacial distribution of lairs and lair types found on refrozen leads and in pressure ridges is described. Lairs were more abundant in inshore ice than in offshore ice. The function of subnivean lairs appears to be to provide thermal shelter, especially for neonate seals, and protection from predation by arctic foxes (Alopex lagopus) and polar bears (Ursus maritimus).

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