scholarly journals Narwhal Abundance in the Eastern Canadian High Arctic in 2013

2020 ◽  
Vol 11 ◽  
Author(s):  
Thomas Doniol-Valcroze ◽  
Jean-François Gosselin ◽  
Daniel G. Pike ◽  
Jack W. Lawson ◽  
Natalie C. Asselin ◽  
...  
Keyword(s):  
Distance Sampling ◽  
High Arctic ◽  
Aerial Survey ◽  
Baffin Island ◽  
Species Identity ◽  
Baffin Bay ◽  
Dive Behaviour ◽  
Declination Angle ◽  
Track Line ◽  
Admiralty Inlet

In summer, narwhals (Monodon monoceros) migrate from Baffin Bay to northeastern Canada and northwest Greenland, where they are hunted by Inuit for subsistence. To prevent localized depletion, management of narwhals is based on summer stocks. The High Arctic Cetacean Survey (HACS), conducted in August 2013, was the first survey to estimate abundance of all 4 Canadian Baffin Bay narwhal summer stocks, as well as putative stocks in Jones Sound and Smith Sound, in the same summer. Narwhal abundance was estimated using a double-platform aerial survey. Distance sampling methods were used to estimate detection probability away from the track line. Mark-recapture methods were used to correct for the proportion of narwhals missed by visual observers on the track line (i.e., perception bias). We used a data-driven approach to identify single and duplicate sightings, using 4 covariates to compare differences in sightings made by front and rear observers based on: time of sighting, declination angle, group size, and species identity. Abundance in fjords was estimated using density surface modelling to account for their complex shape and uneven coverage. Estimates were corrected for availability bias (narwhals that are not available for detection because they are submerged when the aircraft passes overhead) using a new analysis of August dive behaviour data from narwhals equipped with satellite-linked time depth recorders. Corrected abundance estimates were 12,694 (95% CI: 6,324–25,481) for the Jones Sound stock; 16,360 (95% CI: 3,833–69,836) for the Smith Sound stock; 49,768 (95% CI: 32,945–75,182) for the Somerset Island stock; 35,043 (95% CI: 14,188–86,553) for the Admiralty Inlet stock; 10,489 (95% CI: 6,342–17,347) for the Eclipse Sound stock; and 17,555 (95% CI: 8,473–36,373) for the East Baffin Island stock. Total abundance for these 6 stocks was estimated at 141,908 (95% CI: 102,464–196,536). Sources of uncertainty arise from the high level of clustering observed, in particular in Admiralty Inlet, Eclipse Sound, and East Baffin Island, as well as the difficulty in identifying duplicate sightings between observers when large aggregations were encountered.

An on-ice aerial survey of the Kane Basin polar bear (Ursus maritimus) subpopulation

Polar Biology ◽  
2021 ◽  
Author(s):  
Øystein Wiig ◽  
Stephen N. Atkinson ◽  
Erik W. Born ◽  
Seth Stapleton ◽  
Todd Arnold ◽  
...  
Keyword(s):  
Distance Sampling ◽  
Open Water ◽  
High Arctic ◽  
Ursus Maritimus ◽  
Aerial Survey ◽  
Arctic Sea Ice ◽  
Line Transect ◽  
Polar Bears ◽  
The North ◽  
North Water

AbstractThere is an imminent need to collect information on distribution and abundance of polar bears (Ursus maritimus) to understand how they are affected by the ongoing decrease in Arctic sea ice. The Kane Basin (KB) subpopulation is a group of high-latitude polar bears that ranges between High Arctic Canada and NW Greenland around and north of the North Water polynya (NOW). We conducted a line transect distance sampling aerial survey of KB polar bears during 28 April–12 May 2014. A total of 4160 linear kilometers were flown in a helicopter over fast ice in the fjords and over offshore pack ice between 76° 50′ and 80° N′. Using a mark-recapture distance sampling protocol, the estimated abundance was 190 bears (95% lognormal CI: 87–411; CV 39%). This estimate is likely negatively biased to an unknown degree because the offshore sectors of the NOW with much open water were not surveyed because of logistical and safety reasons. Our study demonstrated that aerial surveys may be a feasible method for obtaining abundance estimates for small subpopulations of polar bears.

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.

scholarly journals Estimating brown bear abundance and harvest rate on the southern Alaska Peninsula

PLoS ONE ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. e0245367
Author(s):  
Earl F. Becker ◽  
David W. Crowley
Keyword(s):  
Sampling Method ◽  
Distance Sampling ◽  
Brown Bear ◽  
Aerial Survey ◽  
Abundance Estimation ◽  
Game Management ◽  
Geographic Scale ◽  
Detection Function ◽  
Harvest Rate ◽  
Harvest Data

Abundance estimation of hunted brown bear populations should occur on the same geographic scale as harvest data analyses for estimation of harvest rate. Estimated harvest rates are an important statistic for managing hunted bear populations. In Alaska, harvest data is collected over large geographic units, called Game Management Units (GMUs) and sub-GMUs. These sub GMUs often exceed 10,000 km2. In the spring of 2002, we conducted an aerial survey of GMU 9D (12,600 km2) and GMU 10 (4,070 km2) using distance sampling with mark-resight data. We used a mark-resight distance sampling method with a two-piece normal detection function to estimate brown bear abundance as 1,682.9 (SE = 174.29) and 316.9 (SE = 48.25) for GMU 9D and GMU 10, respectively. We used reported hunter harvest to estimate harvest rates of 4.35% (SE = 0.45%) and 3.06% (SE = 0.47%) for GMU 9D and GMU 10, respectively. Management objective for these units support sustained, high quality hunting opportunity which harvest data indicate are met with an annual harvest rate of approximately 5–6% or less.

An Early Tertiary Outcrop in North-Central Baffin Island, Northwest Territories, Canada: Environment and Significance

1972 ◽  
Vol 9 (3) ◽  
pp. 233-238 ◽  
Author(s):  
J. T. Andrews ◽  
J. D. Ives ◽  
G. K. Guennel ◽  
J. L. Wray
Keyword(s):  
Laminated Sediments ◽  
Coarse Grained ◽  
Baffin Island ◽  
Vertical Movements ◽  
North Central ◽  
Baffin Bay ◽  
Ice Cap ◽  
Early Tertiary ◽  
Warm Temperate

A thin, impure limestone was found in situ on Precambrian bedrock at latitude 70°36.6′ N and longitude 75°20′ W some 26 km northwest of the Barnes Ice Cap. The unit consists of undulating laminations composed of alternating fine- and coarse-grained sediment, which are interpreted as a series of algal mats or algal-laminated sediments. An analysis of enclosed palynomorphs indicates the presence of Ulmus, Taxodiutm, Liriodendron, Carpinus, and Engelhardtia plus other genera. On the basis of the microflora a Paleogene age is assigned to the unit. The climate at that time was warm-temperate and the environment suggested is a freshwater marsh or swamp. The outcrop is restricted to a single hill summit and its location suggests considerable Neogene geomorphological activity, primarily river-cutting associated with vertical movements along the western margin of the Davis Strait/Baffin Bay Tift.

The migratory behaviour of narwhals (Monodon monoceros)

2003 ◽  
Vol 81 (8) ◽  
pp. 1298-1305 ◽  
Author(s):  
Mads Peter Heide-Jørgensen ◽  
Rune Dietz ◽  
Kristin L Laidre ◽  
Pierre Richard ◽  
Jack Orr ◽  
...  
Keyword(s):  
Open Water ◽  
High Arctic ◽  
Early Summer ◽  
Canadian High Arctic ◽  
Baffin Bay ◽  
Bay Area ◽  
Monodon Monoceros ◽  
Migratory Routes ◽  
Somerset Island ◽  
Wintering Ground

Sixteen female narwhals (Monodon monoceros) were tracked by satellite in 2000 and 2001 from their summering ground near Somerset Island in the Canadian High Arctic to their wintering ground in central Baffin Bay. The wintering ground location was spatially discrete from another narwhal wintering ground in southern Baffin Bay. Area extent of the summering ground was approximately 9464 km2 and area extent of the wintering ground was 25 846 km2. Two of the narwhals were tracked for more than 12 consecutive months. These whales used three focal areas between their spring and autumn migration: a coastal area in the open-water season in August in the Canadian High Arctic, a wintering area from November through April in the consolidated pack ice of Baffin Bay, and an early summer area in front of the receding fast ice edge in Lancaster Sound. The whales showed remarkable site fidelity to summering grounds and had specific migratory routes that followed sea ice formation and recession.

Geology, Admiralty Inlet, Baffin Island, District of Franklin

1963 ◽  
Author(s):  
R R H Lemon ◽  
R G Blackadar
Keyword(s):  
Baffin Island ◽  
Admiralty Inlet

MARINE MACROPLANKTON FROM THE CANADIAN EASTERN ARCTIC: I. AMPHIPODA AND SCHIZOPODA

1942 ◽  
Vol 20d (1) ◽  
pp. 33-46 ◽  
Author(s):  
M. J. Dunbar
Keyword(s):  
High Arctic ◽  
Atlantic Water ◽  
Amphipod Species ◽  
Hydrographic Data ◽  
Baffin Bay ◽  
West Greenland ◽  
The Difference ◽  
Two Sides ◽  
A New Species ◽  
Polar Water

Twenty-four amphipod species (one a new species), three euphausiids, and two mysids are recorded from the coastal water of the Canadian eastern Arctic. Most of the records are new.The list is representative of a high arctic plankton, giving no evidence of the intrusion of Atlantic water. This is in agreement with the hydrographic observations made, and with available hydrographic data from other sources.The plankton is contrasted with that found in 1936 in Disko Bay, west Greenland, where there appears to be an upwelling of mixed Arctic and Atlantic water. The difference between the plankton of the two sides of Baffin Bay suggests the possibility of distinguishing water of Lancaster Sound (Canadian polar water) from that of west Greenland by means of their planktonic fauna.

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