scholarly journals A genetic comparison of West Greenland and Baffin Island (Canada) walruses: Management implications

2014 ◽  
Vol 9 ◽  
pp. 33 ◽  
Author(s):  
Liselotte Wesley Andersen ◽  
Erik W Born ◽  
Robert EA Stewart ◽  
Rune Dietz ◽  
DW Doidge ◽  
...  
Keyword(s):  
Baffin Island ◽  
Sustainable Harvest ◽  
Baffin Bay ◽  
West Greenland ◽  
Odobenus Rosmarus ◽  
Davis Strait ◽  
Intense Exploitation ◽  
The Relationship ◽  
Genetic Comparison

Until recently Atlantic walruses (Odobenus rosmarus rosmarus) have been subject to relatively intense exploitation in West Greenland. Animals in this stock have also been hunted in Nunavut/Canada. However, the demographic identity of these animals and their connection with walruses in neighbouring areas is poorly resolved, hampering the determination of sustainable harvest levels. It has been suggested that walruses in West Greenland are genetically linked with walruses at SE Baffin Island (Canada) where they are also hunted for subsistence purposes. To determine the relationship(s) between walruses in these areas we conducted a genetic analysis including recent samples from West Greenland, Southeast Baffin Island in western Davis Strait, Hudson Strait in Canada and Northwest Greenland in northern Baffin Bay. Seventeen microsatellite markers were applied to all samples. Walruses in West Greenland and at Southeast Baffin Island did not differ from each other and therefore may be regarded as belonging to the same stock. However, walruses in these two areas differed genetically from both Northwest Greenland and Hudson Strait walruses. These findings support (1) that there are subunits within the range of walruses in the Hudson Strait-Davis Strait-Baffin Bay region and (2) that walruses along E Baffin Island and W Greenland constitute a common population that receive some influx from Hudson Strait. Thus, sustainable catch levels in Southeast Baffin Island (Nunavut) and in West Greenland must be set in light of the finding that they belong to the same stock, which is exploited in these two areas. This requires Canadian-Greenlandic co-management of the W Greenland-SE Baffin Island walrus stock.

scholarly journals Early Tertiary, low-potassium tholeiites from exploration wells on the West Greenland shelf

1987 ◽  
Vol 136 ◽  
pp. 1-25
Author(s):  
N Hald ◽  
J.G Larsen
Keyword(s):  
Baffin Island ◽  
Quaternary Sediments ◽  
The South ◽  
The West ◽  
Baffin Bay ◽  
West Greenland ◽  
Early Tertiary ◽  
Davis Strait ◽  
Low Potassium

Data on the Tertiary basalts in the Davis Strait region are reported from two exploration wells drilled by Arco and Mobil on the West Greenland shelf. Hellefisk 1 (67°53 'N, 56°44'W), situated only 60 km east of the mid-line in Davis Strait, penetrated the upper 690 m of a subaeriallava sequence continuous with the onshore volcanics of Disko and situated beneath 2.3 km of Paleocene to Quaternary sediments. The lavas are feldspar microporphyritic tholeiites and mostly unmetamorphosed despite the presence of laumontite and prehnite in the vesicular top zones. Nukik 2 (65°38'N, 54°46'W) penetrated 150 m of hyaloclastites and tholeiitic olivine dolerite sheets, presumably sills, some 200 km further to the south. These vo1canics are also deeply buried and are of unknown extension. The drilled rocks, except for the much altered hyaloclastites in the Nukik 2 well, have low contents of Ti02 (0.99-2.03%), K2O (0.09-0.18%) and P2O5 (0.08-0.21%), La/Sm ratios less than one and 87Sr/86Sr ratios of 0.7032 to 0.7044. Chemically they are related to the MORB-like picrites of Baffin Island rather than the less depleted tholeiites of West Greenland. In both areas the MORB affinity may be related to eruptions through a strongly attenuated lithosphere associated with the opening of Baffin Bay and Davis Strait.

Early Tertiary basalts from the Labrador Sea floor and Davis Strait region

1989 ◽  
Vol 26 (5) ◽  
pp. 956-968 ◽  
Author(s):  
D. B. Clarke ◽  
B. I. Cameron ◽  
G. K. Muecke ◽  
J. L. Bates
Keyword(s):  
Volcanic Rocks ◽  
Labrador Sea ◽  
Baffin Island ◽  
Nd Isotope ◽  
Sea Floor ◽  
West Greenland ◽  
Depleted Mantle ◽  
Davis Strait ◽  
Isotope Systematics ◽  
Seawater Exchange

Fine- to medium-grained, phyric and aphyric basalt samples from ODP Leg 105, site 647A, in the Labrador Sea show little evidence of alteration. Chemically, these rocks are low-potassium (0.01–0.09 wt.% K2O), olivine- to quartz-normative tholeiites that compare closely with the very depleted terrestrial Paleocene volcanic rocks in the Davis Strait region of Baffin Island and West Greenland. However, differences exist in the Sr–Nd isotope systematics of the two suites; the Labrador Sea samples have ε Nd values (+9.3) indicative of a more depleted source, and are higher in 87Sr/86Sr (0.7040), relative to the Davis Strait basalts (ε Nd +2.54 to +8.97; mean 87Sr/86Sr 0.7034). The higher 87Sr/86Sr in the Labrador Sea samples may reflect seawater exchange despite no petrographic evidence for significant alteration. The Labrador Sea and early Davis Strait basalts may have been derived from a similar depleted mantle source composition; however, the later Davis Strait magmas were generated from a different mantle. None of the Baffin Island, West Greenland, or Labrador Sea samples show unequivocal geochemical evidence for contamination with continental crust.

scholarly journals Volume, Freshwater, and Heat Fluxes through Davis Strait, 2004–05*

2011 ◽  
Vol 41 (3) ◽  
pp. 429-436 ◽  
Author(s):  
B. Curry ◽  
C. M. Lee ◽  
B. Petrie
Keyword(s):  
Heat Fluxes ◽  
First Year ◽  
Baffin Island ◽  
Fram Strait ◽  
The West ◽  
Baffin Bay ◽  
Freshwater Fluxes ◽  
Davis Strait ◽  
Island Shelf ◽  
Southward Transport

Abstract Davis Strait volume [−2.3 ± 0.7 Sv (1 Sv ≡ 106 m3 s−1); negative sign indicates southward transport], freshwater (−116 ± 41 mSv), and heat (20 ± 9 TW) fluxes estimated from objectively mapped 2004–05 moored array data do not differ significantly from values based on a 1987–90 array but are distributed differently across the strait. The 2004–05 array provided the first year-long measurements in the upper 100 m and over the shelves. The upper 100 m accounts for 39% (−0.9 Sv) of the net volume and 59% (−69 mSv) of the net freshwater fluxes. Shelf contributions are small: 0.4 Sv (volume), 15 mSv (freshwater), and 3 TW (heat) from the West Greenland shelf and −0.1 Sv, −7 mSv, and 1 TW from the Baffin Island shelf. Contemporaneous measurements of the Baffin Bay inflows and outflows indicate that volume and freshwater budgets balance to within 26% and 4%, respectively, of the net Davis Strait outflow. Davis Strait volume and freshwater fluxes nearly equal those from Fram Strait, indicating that both are significant Arctic freshwater pathways.

scholarly journals An overview of genetic relationships of Canadian and adjacent populations of belugas (Delphinapterus leucas) with emphasis on Baffin Bay and Canadian eastern Arctic populations

2002 ◽  
Vol 4 ◽  
pp. 17 ◽  
Author(s):  
BGE De March ◽  
L D Maiers ◽  
M K Friesen
Keyword(s):  
Current Knowledge ◽  
Genetic Relationships ◽  
High Arctic ◽  
Small Sample ◽  
Delphinapterus Leucas ◽  
Baffin Island ◽  
Genetic Characteristics ◽  
Baffin Bay ◽  
West Greenland ◽  
Small Sample Sizes

Our current knowledge of the molecular genetics of High Arctic beluga (Delphinapterus leucas) populations (West Greenland, Lancaster Sound/Barrow Strait, Grise Fiord) and populations that are related (southeast Baffin, Beaufort Sea), is presented. In general, genetic analyses confirm the designation of putative stocks and suggest the existence of more stocks than previously described. Comparisons based on mitochondrial DNA haplotypes show that West Greenland (1992) belugas were significantly differentiated from Lancaster Sound/Barrow Strait, Kimmirut, Iqaluit, and/or Pangnirtung but not from Grise Fiord. Grise Fiord haplotypes were not significantly differentiated from Lancaster Sound/Barrow Strait and not from southeast Baffin locations in some years. Lancaster Sound and southeast Baffin collections were not significantly differentiated from each other. These patterns existed for most years within locations, however a few yearly collections within major locations had different patterns. The collections that differed were small groups with few haplotypes, most likely relatives. Patterns in microsatellite differentiation were slightly different than those for haplotypes. This may be due to the fact that individuals in sampled summering populations breed with individuals in other populations during migration or in overwintering areas. West Greenland and Grise Fiord microsatellites were not significantly differentiated from each other. However, Greenland differed from Lancaster Sound and southeast Baffin Island, while Grise Fiord did not. In southeast Baffin Island, Pangnirtung samples differed from Kimmirut using both haplotypes and microsatellites. Iqaluit samples had intermediate genetic characteristics between Pangnirtung and Kimmirut. Patterns of significant differentiation among collections within locations was believed to be due to a combination of temporal patterns, sampling of relatives, chance, seasonal hunting, small sample sizes, and actual differences among populations.

Paleomagnetic Results on Early Tertiary Lava Flows from West Greenland and their bearing on the Evolution History of the Baffin Bay–Labrador Sea Region

1975 ◽  
Vol 12 (1) ◽  
pp. 1-18 ◽  
Author(s):  
R. N. Athavale ◽  
P. V. Sharma
Keyword(s):  
Pole Position ◽  
Ocean Basin ◽  
Lava Flows ◽  
Labrador Sea ◽  
Baffin Island ◽  
Baffin Bay ◽  
West Greenland ◽  
Early Tertiary ◽  
History Of ◽  
The One

Paleomagnetic investigations have been carried out on about 250 oriented block samples collected from Early Tertiary lava flows representing an altitude span of about 1200 m on the Disko Island and 600 m on the Nûgssuaq Peninsula of West Greenland. The results reveal a record of two polarity transitions on the Disko Island and the existence of normal (N) and reverse (R) groups of lava flows on the Nûgssuaq Peninsula. A tentative correlation of the lava sequences from the two areas, on the basis of polarity of magnetization, has been suggested. Subject to the assumption of relatively uniform extrusion rates in northern Disko, a correlation of the comparatively thick sequence of reverse (R) polarity flows with the relatively long reverse epoch between the anomaly no. 25 (ca. 63 m.y.) and anomaly no. 24 (ca. 60.5 m.y.B.P.), has been attempted and an age estimate of the lava flows has been obtained.The Early Tertiary paleomagnetic pole for Greenland, computed from stable remanent magnetic directions of the Disko lavas is located at 67.5 °N and 165 °W. This pole position and the one for contemporaneous lava flows on the Baffin Island of Canada have been used in testing the models proposed by various workers for a paleogeographic reconstruction of Greenland and Canada, involving a closure of the Baffin Bay – Labrador Sea. The results of this paleomagnetic test suggest the existence of an ocean basin in the area, prior to the eruption of Early Tertiary lava sequences on Baffin Island and West Greenland, and also that this ocean basin had a much wider extent in Pre-Tertiary times.A model for the evolution of Baffin Bay – Labrador Sea has been suggested in the light of available geological/geophysical information about the region. It involves the opening of this sea in the Mesozoic and its partial closure during the Cenozoic as a consequence of the drift of Greenland in the northwesterly direction.

scholarly journals Population dynamics of walruses in Greenland

2014 ◽  
Vol 9 ◽  
pp. 191 ◽  
Author(s):  
Lars Witting ◽  
Erik Born
Keyword(s):  
Baffin Island ◽  
Continuous Increase ◽  
East Greenland ◽  
Baffin Bay ◽  
West Greenland ◽  
Structure Information ◽  
Abundance Estimate ◽  
Structured Population Models ◽  
Abundance Estimates ◽  
The 1960S

The historical and current dynamics of the three Atlantic walrus (Odobenus rosmarus rosmarus) populations that occur in Greenland are estimated using age- and sex-structured population models with exponential growth, density-regulated growth and selection-delayed dynamics. These models are integrated with data in a Bayesian framework, where the likelihood of the simulated population trajectories are evaluated from recent abundance estimates and age-structure information from a selective hunt. The overall decline in the Baffin Bay population caused by historical catches is unclear due to incomplete catch reporting prior to 1950s. However, it is estimated that the population declined by 40% from the 1960s to 2005; decreased catches (≈ 140 to ≈ 70) have subsequently allowed this population to increase. The 2012 abundance estimate is 1,400 (95% CI: 1,000-2,000) individuals, and the annual natural growth rate in this population is now 7.7% (95% CI: 6.7-8.9%). Averaging across models, it is estimated that West Greenland/Baffin Island walruses declined by 80% from 7,000 (95% CI: 5,400-10,000) in 1900 to 1,350 (CI: 950-1,950) in 1960. Hereafter they increased to 3,100 (95% CI: 2,500-4,400) in 1993, and owing to increased catches they have experienced a minor decline between 1994 and the early 2000s. Annual catches where then cut from 190 to the current quota of 61, and the population is again increasing with a 2012 estimate of 3,900 (95% CI: 2,500-5,300) individuals. A 2012 estimate of 1,400 (95% CI: 700-3,100) walruses in East Greenland is recovered relative to 1888; the year prior to our first historical catches by European sealers. The historical trajectory, however, is uncertain: Density regulation estimates a relatively flat trajectory, with a maximal depletion in 1890 to 80% of the initial abundance, and a slow continuous increase to almost no current growth. A recovered population is also estimated by selection-delayed dynamics. However, this model estimates a continued increase, and a historical depletion to 2% in 1957. These results are only partially comparable with an earlier assessment for East Greenland. Updated abundance estimates for West Greenland, and modelling with age-structured data from Baffin Bay, have greatly improved our status estimates for Baffin Bay and West Greenland/Baffin Island.

scholarly journals Abundance of walruses in Eastern Baffin Bay and Davis Strait

2014 ◽  
Vol 9 ◽  
pp. 159 ◽  
Author(s):  
Mads Peter Heide-Jørgensen ◽  
Kristin Laidre ◽  
Sabrina Fossette ◽  
Marianne H Rasmussen ◽  
Nynne Hjort Nielsen ◽  
...  
Keyword(s):  
Correction Factor ◽  
Pressure Transducer ◽  
Detection Threshold ◽  
Wintering Grounds ◽  
Baffin Bay ◽  
Current Information ◽  
Aerial Surveys ◽  
Odobenus Rosmarus ◽  
Abundance Estimates ◽  
Davis Strait

Walruses (Odobenus rosmarus) are exploited for subsistence purposes in West Greenland. However, current information about the abundance of walruses subject to harvest in eastern Baffin Bay subject to harvest has been unavailable despite being critical for maintaining sustainable catch levels. Three visual aerial surveys were conducted in 2006 (21 March to 19 April 2006), 2008 (3 to 12 April) and 2012 (24 March to 14 April) to estimate the number of walruses on the wintering grounds in eastern Baffin Bay and Davis Strait. Data on the fraction of walruses that were submerged below a 2m detection threshold during the surveys were obtained from 24 walruses instrumented with satellite-linked-time-depth-recorders in northern Baffin Bay in May-June 2010-2012. An availability correction factor was estimated at 36.5% (cv=0.08) after filtering of data for an observed drift of the pressure transducer of more than 2.5 m. The surveys resulted in walrus abundance estimates that were corrected for walruses submerged below a detection threshold and for walruses that were missed by the observers. The estimates of abundance were 1,105 (cv=0.31, 95% CI 610-2,002) in 2006, 1,137 (0.48, 468-2,758) in 2008 and 1,408 (0.22, 922-2,150) in 2012. 

scholarly journals The variability of Baffin Bay seafloor sediment mineralogy: the identification of discrete glacial sediment sources and application to Late Quaternary downcore analysis

2018 ◽  
Vol 55 (6) ◽  
pp. 620-639 ◽  
Author(s):  
John T. Andrews ◽  
Anna J. Klein ◽  
Kimberly A. Jenner ◽  
Anne E. Jennings ◽  
Calvin Campbell
Keyword(s):  
Grain Size ◽  
Late Quaternary ◽  
Baffin Island ◽  
Sediment Sources ◽  
The West ◽  
Regional Patterns ◽  
Size Spectra ◽  
Baffin Bay ◽  
West Greenland ◽  
Mineral Assemblages

Quantitative X-ray diffraction (qXRD) mineralogy of bedrock, ice-rafted, and fluvial clasts, 239 seafloor samples (<2 mm), and samples from two long piston cores were used to (i) define regional patterns and sources within Baffin Bay, (ii) evaluate two areas from west Greenland and east Baffin Island in more detail, and (iii) apply these findings to the interpretation of downcore variations in sediment sources. A sediment-unmixing program is used to define surface regional mineral assemblages and to examine changes in sediment sources in cores HU2013029-77PC (southern Baffin Island slope) and HU2008029-8PC (Davis Strait) during Marine Isotope Stages 1 through 3. Distinct regional patterns are observed in the association between the mineralogy of surface sediments and carbonate and basalt bedrock outcrops. Detailed analysis of seafloor samples from the west Greenland troughs and Baffin Island fjords show regional differences in mineralogy, with sediments derived from the Foxe Fold Belt (north-central Baffin Island) being mineralogically distinct from sediments to the north and south. Grain-size spectra from the west Greenland troughs suggested an association between grain-size spectra and mineral assemblages. Sediment unmixing of qXRD data from the two piston cores shows discrete intervals where one or more mineral sources were dominant. However, chronological control is such that it is unclear whether the various ice streams draining into Baffin Bay behaved synchronously.

Tertiary Basalts of Baffin Island: Field Relations and Tectonic Setting

1971 ◽  
Vol 8 (2) ◽  
pp. 248-258 ◽  
Author(s):  
D. B. Clarke ◽  
B. G. J. Upton
Keyword(s):  
Tectonic Setting ◽  
Continental Drift ◽  
Labrador Sea ◽  
Baffin Island ◽  
Precambrian Basement ◽  
Baffin Bay ◽  
West Greenland ◽  
Magma Type ◽  
Terrestrial Sediments ◽  
Stratigraphic Position

This paper describes the field relations of Tertiary basalts which are preserved as small patches intermittently along the coast for 90 km northwest from Cape Dyer, Baffin Island. The flat-lying, subaerial lavas generally rest directly on the Precambrian basement but in some localities a thin sequence of terrestrial sediments intervenes between the basement and the volcanics. Where the sediments occur, the overlying volcanics tend to be divisible into a lower unit of subaqueous volcanic breccia and an upper sequence of subaerial flows. In age, stratigraphic position and magma-type, these volcanics strongly resemble those of the basalt province of west Greenland. A model is presented for the generation of both provinces in a single volcanic episode, related to the opening of Labrador Sea – Baffin Bay by continental drift.

Bowhead whaling in Davis Strait and Baffin Bay during the 18th and 19th Centuries

Polar Record ◽  
1986 ◽  
Vol 23 (144) ◽  
pp. 289-299 ◽  
Author(s):  
Richard Vaughan
Keyword(s):  
Quantitative Data ◽  
Current Knowledge ◽  
Baffin Bay ◽  
West Greenland ◽  
Davis Strait ◽  
History Of

ABSTRACTHistories of individual whale fisheries mainly undertaken by Europeans have yet to be written. This article provides an outline history of whaling in the Davis Strait area during the 18th and 19th centuries. Current knowledge is reviewed of whaling west of Greenland by ships from Danish, Dutch and German ports, and from English, American and Scottish ports. The land-based West Greenland whale fishery is also mentioned, and the activities of whalers from France and Spain. In spite of recent national whaling histories of the English, Dutch and Danish industries, quantitative data for the Davis Strait fishery are still virtually non-existent.

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