Distribution and Abundance of Belugas, Delphinapterus leucas, and Narwhals, Monodon monoceros, in the Canadian High Arctic

1985 ◽  
Vol 42 (4) ◽  
pp. 676-684 ◽  
Author(s):  
T. G. Smith ◽  
M. O. Hammsll ◽  
D. J. Burrage ◽  
G. A. Sleno

Opportunistic reconnaissance aerial surveys of Lancaster Sound, Barrow Strait, Peel Sound, and Prince Regent Inlet were conducted between 1974 and 1982 to determine the distribution and abundance of belugas, Delphinapterus leucas, and narwhals, Monodon monoceros. In 1981, two stratified strip-transect surveys were flown. From these we estimate that a total of 6300 – 18 600 belugas and approximately 13 200 –18 000 narwhals summer in Lancaster Sound and adjoining waterways. Improvement in the precision of these estimates would require a substantial increase in survey coverage and may not be justified considering the significant increase in costs. Our review of the results of surveys conducted since 1975 in the same study area, of which most of the information is not yet available in the scientific literature, shows much duplication of effort, little increase in information, and a lack of confidence limits for the estimated numbers.

1994 ◽  
Vol 51 (7) ◽  
pp. 1653-1663 ◽  
Author(s):  
Thomas G. Smith ◽  
A. R. Martin

Belugas, Delphinapterus leucas, move into the coastal waters of Somerset Island as soon as the annual land-fast ice breaks up in late June – early July. Six bays or inlets which receive the outflow of rivers are the major areas of summer aggregation. Belugas captured and equipped with satellite-linked UHF transmitters in Cunningham Inlet (Barrow Strait), Elwin Bay (Prince Regent Inlet), and Creswell Bay moved west into Peel Sound where they frequented two other estuaries. Rapid and directed movement out of Peel Sound occurred in late August. All of the animals which transmitted locations into September or October moved to eastern Devon Island and Jones Sound. The longest period of transmission was 75 d, lasting until mid-October. Belugas tagged in three different locations around Somerset Island in the summers of 1988–93 showed a well-defined and consistent pattern of behaviour. Aerial surveys done during this period confirm that the vast majority of belugas in this region are involved in these seasonal movements.


2003 ◽  
Vol 81 (8) ◽  
pp. 1298-1305 ◽  
Author(s):  
Mads Peter Heide-Jørgensen ◽  
Rune Dietz ◽  
Kristin L Laidre ◽  
Pierre Richard ◽  
Jack Orr ◽  
...  

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.


1986 ◽  
Vol 43 (10) ◽  
pp. 1982-1987 ◽  
Author(s):  
T. G. Smith ◽  
M. O. Hammill

Coastal reconnaissance and systematic aerial surveys of white whales, Delphinapterus leucas, were flown in James Bay, eastern Hudson Bay, and Ungava Bay. In Ungava Bay the numbers of belugas are so low that we are unable to derive population estimates. In James Bay, we estimate 1213 whales with 95% confidence limits of 740–1970 individuals. In eastern Hudson Bay our systematic survey estimates 968 whales (650–1430), with an additional 474 whales counted in traditional areas of coastal concentration. The age structure of whales inshore and offshore appears similar. Our estimates are conservative, since they do not include a correction for animals which might have been underwater as we passed. Since belugas continue to be hunted in Ungava Bay and eastern Hudson Bay, recommendations are made for a conservative management strategy which must soon be implemented.


2020 ◽  
Vol 36 (2) ◽  
pp. 451-471 ◽  
Author(s):  
Paul Szpak ◽  
Marie‐Hélène Julien ◽  
Thomas C. A. Royle ◽  
James M. Savelle ◽  
Dongya Y. Yang ◽  
...  

2002 ◽  
Vol 80 (4) ◽  
pp. 624-635 ◽  
Author(s):  
Kristin L Laidre ◽  
Mads Peter Heide-Jørgensen ◽  
Rune Dietz

In August 1999 and 2000, four suction-cup-attached time–depth recorders (TDRs) were deployed and retrieved from narwhals (Monodon monoceros) in Tremblay Sound, Baffin Island, and Creswell Bay, Somerset Island, Nunavut, Canada. The TDRs remained on the whales for between 12 and 33 h and collected 64.5 h of dive data. Mean dive depths ranged from 20.8 m (SD = 14.8 m) to 50.8 m (SD = 43.8 m) and mean dive durations ranged from 3.4 min (SD = 1.6 min) to 4.9 min (SD = 4.5 min). There appeared to be individual differences in dive parameters both within a region and between regions. Three of the whales made short, shallow dives, while another whale made dives twice as deep and twice as long. One whale had maximum dive durations (>20 min) that exceeded predicted aerobic dive limits for narwhals. There was a strong relationship between maximum dive depth and duration for all whales (p < 0.0001). Narwhals spent between 30.3 and 52.9% of their time at depths <5 m and the range of correction factors for availability bias was 1.9–3.3. Satellite-linked TDRs were simultaneously deployed on the whales at both localities. Dive data collected using the two methods were compared and good agreement between the methods was obtained.


Polar Biology ◽  
2003 ◽  
Vol 26 (5) ◽  
pp. 318-326 ◽  
Author(s):  
M. P. Heide-Jørgensen ◽  
P. Richard ◽  
R. Dietz ◽  
K. L. Laidre ◽  
J. Orr ◽  
...  

2002 ◽  
Vol 4 ◽  
pp. 169 ◽  
Author(s):  
Stuart Innes ◽  
MP Heide-Jørgensen ◽  
Jeff L Laake ◽  
Kristin L Laidre ◽  
Holly J Cleator ◽  
...  

The summer range of belugas (Delphinapterus leucas) and narwhals (Monodon monoceros) in Prince Regent Inlet, Barrow Strait and Peel Sound in the Canadian High Arctic was surveyed from 31 July to 3 August 1996 with a visual aerial survey of offshore areas and photographic aerial surveys of concentration areas. The visual survey estimate based on the number of belugas visible to the observers using systematic line transect methods was 10,347 (cv = 0.28). This included corrections for whales that were missed by the observers, observations without distance measurements and an estimate of 1,949 (cv=0.22) belugas from a photographic survey in southern Peel Sound. Using data from belugas tagged with satellite-linked time-depth recorders, the estimate was adjusted for individuals that were diving during the survey which resulted in an estimate of 18,930 belugas (cv = 0.28). Finally, counts of belugas in estuaries, corrected for estuarine surface time, were added to provide a complete estimate of 21,213 belugas (95% CI 10,985 to 32,619). The estimated number of narwhals corrected for sightings that were missed by observers was 16,364 (cv = 0.24). Adjusting this for sightings without distance information and correcting for whales that were submerged produced an estimate of 45,358 narwhals (95% CI 23,397 to 87,932).


2007 ◽  
Vol 39 (8) ◽  
pp. 1794-1811 ◽  
Author(s):  
Richard C Powell

The author examines the development of the notion of the field experiment in High Arctic environmental sciences during the period 1958–70. After a discussion of the philosophy and sociology of experiment, the author considers a set of field practices conducted under the auspices of the Canadian Government's Polar Continental Shelf Project. Drawing on archival and oral historical research, he argues that field scientists had to deal with a number of logistical, corporeal, and epistemic difficulties in the High Arctic. It is demonstrated that these obstacles hindered attempts to develop a scientific literature based upon experimental practices during fieldwork. In doing so, the author attempts to set new agendas for historical geographers of science around the analysis of the geographical sciences, whilst also contributing to discussions about the epistemic status of variegated field practices.


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