Deep Diving in Wild, Free-Ranging Beluga Whales, Delphinapterus leucas

1992 ◽  
Vol 49 (3) ◽  
pp. 462-466 ◽  
Author(s):  
A. R. Martin ◽  
T. G. Smith
Keyword(s):  
Upper Bound ◽  
Ambient Pressure ◽  
High Arctic ◽  
Delphinapterus Leucas ◽  
Canadian High Arctic ◽  
Near Surface ◽  
Beluga Whales ◽  
Deep Diving ◽  
Radio Transmitters ◽  
Free Ranging

Three adult female beluga whales, Delphinapterus leucas, were captured during summer in the Canadian high Arctic and equipped with satellite-linked radio transmitters that measured and recorded ambient pressure every 20 s. Diving behaviour was divisible into three distinct categories: (1) near-surface, (2) "spike" dives to 20–150 m depth, and (3) prolonged, flat-bottomed dives to a maximum depth of 350 m. The duration of these prolonged dives was 9.3–13.7 min, but the upper bound is known to be underestimated. Average descent rates varied between dives in the range 1.43–2.20 m/s and ascent rates between 1.23 and 1.84 m/s. Within periods of 20 s duration, maximum descent and ascent rates were 2.55 and 2.35 m/s, respectively. After most prolonged dives the rate of ascent declined progressively as the surface was approached, particularly in the final 100 m. Such dives were usually to, or near to, the seabed and were probably for foraging. Up to 42% of an animal's time could be spent at depths of 8 m or more.

Sexual differences in the foraging ecology of 19th century beluga whales ( Delphinapterus leucas ) from the Canadian High Arctic

2020 ◽  
Vol 36 (2) ◽  
pp. 451-471 ◽  
Author(s):  
Paul Szpak ◽  
Marie‐Hélène Julien ◽  
Thomas C. A. Royle ◽  
James M. Savelle ◽  
Dongya Y. Yang ◽  
...  
Keyword(s):  
19Th Century ◽  
Foraging Ecology ◽  
High Arctic ◽  
Sexual Differences ◽  
Delphinapterus Leucas ◽  
Canadian High Arctic ◽  
Beluga Whales

scholarly journals A trajectory analysis of atmospheric transport of black carbon aerosols to Canadian High Arctic in winter and spring (1990–2005)

2010 ◽  
Vol 10 (2) ◽  
pp. 2221-2244 ◽  
Author(s):  
L. Huang ◽  
S. L. Gong ◽  
S. Sharma ◽  
D. Lavoué ◽  
C. Q. Jia
Keyword(s):  
Regression Model ◽  
Black Carbon ◽  
North American ◽  
Emission Intensity ◽  
Atmospheric Transport ◽  
High Arctic ◽  
The Arctic ◽  
Canadian High Arctic ◽  
Near Surface ◽  
Annual Variations

Abstract. Black carbon (BC) particles accumulated in the Arctic troposphere and deposited over snow have significant effects on radiative forcing of the Arctic regional climate. Applying cluster analysis technique on 10-day backward trajectories, transport pathways affecting Alert (82.5° N, 62.5° W), Nunavut in Canada are identified in this work, along with the associated transport frequency. Based on the atmospheric transport frequency and the estimated BC emission intensity from surrounding regions, a linear regression model is constructed to investigate the inter-annual variations of BC observed at Alert in January and April, representative of winter and spring respectively, between 1990 and 2005. Strong correlations are found between BC concentrations predicted with the regression model and measured at Alert for both seasons (R2 equals 0.77 and 0.81 for winter and spring, respectively). Results imply that atmospheric transport and BC emission are the major contributors to the inter-annual variations in BC concentrations observed at Alert in the cold seasons for the 16-year period. Based on the regression model the relative contributions of regional BC emissions affecting Alert are attributed to the Eurasian sector, composed of the European Union and the former USSR, and the North American sector. Considering both seasons, the model suggests that Eurasia is the major contributor to the near-surface BC levels at the Canadian High Arctic site with an average contribution of over 85% during the 16-year period. In winter, the atmospheric transport of BC aerosols from Eurasia is found to be even more predominant with a multi-year average of 94%. The model estimates smaller contribution from the Eurasian sector in spring (70%) than that in winter. It is also found that the change in Eurasian contributions depends mainly on the reduction of emission intensity, while the changes in both emission and atmospheric transport contributed to the inter-annual variation of North American contributions.

Sexing beluga whales (Delphinapterus leucas) by means of DNA markers

1991 ◽  
Vol 69 (7) ◽  
pp. 1971-1976 ◽  
Author(s):  
Moira W. Brown ◽  
Ree Helbig ◽  
Peter T. Boag ◽  
David E. Gaskin ◽  
Bradley N. White
Keyword(s):  
Y Chromosome ◽  
Zinc Finger Protein ◽  
Restriction Enzymes ◽  
Delphinapterus Leucas ◽  
Gene Probe ◽  
Beluga Whales ◽  
Zinc Finger Protein Gene ◽  
Dna Restriction ◽  
Male Specific ◽  
Free Ranging

Few methods are available for determining the sex of free-ranging individual whales, dolphins, and porpoises of species that are not obviously sexually dimorphic. We have developed a technique for sexing beluga whales (Delphinapterus leucas) by using a Y-chromosome-specific DNA restriction fragment. Genomic DNA was extracted from liver samples of 18 beluga whales (9 males, 9 females) sexed at dissection. DNA from males and females was digested with five restriction enzymes, electrophoresed, and transferred to membranes by Southern blotting. When probed with the labelled human Y-chromosome zinc finger protein gene probe pDP1007, male-specific bands and bands common to both sexes, but more intense in females than in males, were observed. The DNA digested with EcoRI provided the clearest sex-discriminating banding pattern. Even when DNA of various qualities digested with EcoRI was used, all the males showed a 3.4-kilobase (kb) band, presumably from the Y-chromosome, as well as a 2.1-kb band. Females showed the 2.1-kb band, but all lacked the 3.4-kb band. This 3.4-kb EcoRI male-specific band permits unambiguous sex determination, which will facilitate examination of sex-related differences in population structure and habitat use of belugas, which have important implications for management decisions.

scholarly journals Water tracks in the High Arctic: a hydrological network dominated by rapid subsurface flow through patterned ground

2017 ◽  
Vol 3 (2) ◽  
pp. 334-353 ◽  
Author(s):  
Michel Paquette ◽  
Daniel Fortier ◽  
Warwick F. Vincent
Keyword(s):  
Active Layer ◽  
Cold Water ◽  
High Arctic ◽  
Canadian High Arctic ◽  
Patterned Ground ◽  
Arctic Water ◽  
Near Surface ◽  
Polar Desert ◽  
Flow Through

Water tracks play a major role in the headwater basin hydrology of permafrost landscapes in Alaska and Antarctica, but less is known about these features in the High Arctic. We examined the physical and hydrological properties of water tracks on Ward Hunt Island, a polar desert site in the Canadian High Arctic, to evaluate their formation process and to compare with water tracks reported elsewhere. These High Arctic water tracks flowed through soils that possessed higher near-surface organic carbon concentrations, higher water content, and coarser material than the surrounding soils. The water track morphology suggested they were initiated by a combination of sorting, differential frost heaving, and eluviation. The resultant network of soil conduits, comparable to soil pipes, dominated the hydrology of the slope. The flow of cold water through these conduits slowed down the progression of the thawing front during summer, making the active layer consistently shallower relative to adjacent soils. Water tracks on Ward Hunt Island, and in polar desert catchments with these features elsewhere in the High Arctic, strongly influence slope hydrology and active-layer properties while also affecting vegetation distribution and the quality of runoff to the downstream lake.

scholarly journals Larger body size leads to greater female beluga fitness at the southern periphery of their range

2020 ◽  
Author(s):  
Steven Ferguson ◽  
David Yurkowski ◽  
Justine Hudson ◽  
Tera Edkins ◽  
Cornelia Willing ◽  
...  
Keyword(s):  
Body Size ◽  
Body Length ◽  
High Arctic ◽  
Delphinapterus Leucas ◽  
Causal Mechanism ◽  
Hudson Bay ◽  
Peripheral Populations ◽  
Beluga Whales ◽  
Future Challenges ◽  
Variation Explained

Identifying phenotypic characteristics of evolutionarily fit individuals provides important insight into the evolutionary processes that cause range shifts with climate warming. Female beluga whales (Delphinapterus leucas) from the Canadian high Arctic (BB) residing in the core region of the species’ geographic range are 14% larger than their conspecifics at the southern periphery in Hudson Bay (HB). We investigated the causal mechanism for this north (core)-south (periphery) difference as it relates to fitness by combining morphometric data with ovarian corpora counted in female reproductive tracts. We found evidence for reproductive senescence in older HB females from the southern peripheral population but not for BB whales. Female beluga whale fitness in the more-northern BB increased faster with age (48% partial variation explained) versus a more gradual slope (25%) in HB. In contrast, body length in HB female beluga accounted for five times more of the total variation in fitness compared to BB whales. We speculate that female HB beluga fitness was more strongly linked with body length due to higher density, as larger body size provides survival advantages during seasonal food limitations. Understanding the evolutionary mechanism of how fitness changes will assist conservation efforts in anticipating and mitigating future challenges to peripheral populations.

scholarly journals Vertical sonar beam width and scanning behavior of wild belugas (Delphinapterus leucas) in West Greenland

PLoS ONE ◽  
2021 ◽  
Vol 16 (9) ◽  
pp. e0257054
Author(s):  
Marie J. Zahn ◽  
Kristin L. Laidre ◽  
Peter Stilz ◽  
Marianne H. Rasmussen ◽  
Jens C. Koblitz
Keyword(s):  
Beam Width ◽  
The Arctic ◽  
Delphinapterus Leucas ◽  
Recording Equipment ◽  
West Greenland ◽  
Beluga Whales ◽  
Pack Ice ◽  
Scanning Behavior ◽  
Hydrophone Array ◽  
Free Ranging

Echolocation signals of wild beluga whales (Delphinapterus leucas) were recorded in 2013 using a vertical, linear 16-hydrophone array at two locations in the pack ice of Baffin Bay, West Greenland. Individual whales were localized for 4:42 minutes of 1:04 hours of recordings. Clicks centered on the recording equipment (i.e. on-axis clicks) were isolated to calculate sonar parameters. We report the first sonar beam estimate of in situ recordings of wild belugas with an average -3 dB asymmetrical vertical beam width of 5.4°, showing a wider ventral beam. This narrow beam width is consistent with estimates from captive belugas; however, our results indicate that beluga sonar beams may not be symmetrical and may differ in wild and captive contexts. The mean apparent source level for on-axis clicks was 212 dB pp re 1 μPa and whales were shown to vertically scan the array from 120 meters distance. Our findings support the hypothesis that highly directional sonar beams and high source levels are an evolutionary adaptation for Arctic odontocetes to reduce unwanted surface echoes from sea ice (i.e., acoustic clutter) and effectively navigate through leads in the pack ice (e.g., find breathing holes). These results provide the first baseline beluga sonar metrics from free-ranging animals using a hydrophone array and are important for acoustic programs throughout the Arctic, particularly for acoustic classification between belugas and narwhals (Monodon monoceros).

An estimate of the fraction of belugas (Delphinapterus leucas) in the Canadian high Arctic that winter in West Greenland

Polar Biology ◽  
2003 ◽  
Vol 26 (5) ◽  
pp. 318-326 ◽  
Author(s):  
M. P. Heide-Jørgensen ◽  
P. Richard ◽  
R. Dietz ◽  
K. L. Laidre ◽  
J. Orr ◽  
...  
Keyword(s):  
High Arctic ◽  
Delphinapterus Leucas ◽  
Canadian High Arctic ◽  
West Greenland

scholarly journals Surveys of belugas and narwhals in the Canadian High Arctic in 1996

2002 ◽  
Vol 4 ◽  
pp. 169 ◽  
Author(s):  
Stuart Innes ◽  
MP Heide-Jørgensen ◽  
Jeff L Laake ◽  
Kristin L Laidre ◽  
Holly J Cleator ◽  
...  
Keyword(s):  
High Arctic ◽  
Aerial Survey ◽  
Delphinapterus Leucas ◽  
Line Transect ◽  
Canadian High Arctic ◽  
Distance Measurements ◽  
Distance Information ◽  
Surface Time ◽  
Summer Range ◽  
Using Data

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).

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