Foraging ecology of ringed seals (Pusa hispida), beluga whales (Delphinapterus leucas) and narwhals (Monodon monoceros) in the Canadian High Arctic determined by stomach content and stable isotope analysis

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.

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

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f92-055 ◽

1992 ◽

Vol 49 (3) ◽

pp. 462-466 ◽

Cited By ~ 40

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.

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Subcolony Variation in Breeding Success in the Tufted Puffin (Fratercula Cirrhata): Association With Foraging Ecology and Implications

The Auk ◽

10.1093/auk/124.4.1149 ◽

2007 ◽

Vol 124 (4) ◽

pp. 1149-1157

Author(s):

J. Mark Hipfner ◽

Mathieu R. Charette ◽

Gwylim S. Blackburn

Keyword(s):

Stable Isotope ◽

Breeding Success ◽

Large Scale ◽

Foraging Ecology ◽

Isotope Analysis ◽

Egg Yolk ◽

Foraging Strategies ◽

Small Scale ◽

Carbon And Nitrogen ◽

Tufted Puffin

Abstract Large-scale oceanographic processes are the main drivers of seabird breeding success, but small-scale processes, though not as well understood, can also be important. We compared the success of Tufted Puffins (Fratercula cirrhata) breeding at two subcolonies only 1.5 km apart on Triangle Island, British Columbia, Canada, 2002–2005. In addition, we used stable-isotope analysis to test the hypothesis that parental foraging strategies differed between the two subcolonies, potentially underlying the variation in breeding success. Success was concordant across years at the two sites but, overall, Tufted Puffins bred more successfully at Strata Rock than at Puffin Rock. They raised chicks in all four years at Strata Rock, but in only three years at Puffin Rock; in two of those three years, Strata Rock chicks were, on average, 60 g and 100 g heavier than Puffin Rock chicks just before fledging. Discriminant analysis of carbon and nitrogen stable-isotope ratios in egg yolk and chick blood in 2004 and 2005 indicated that parental foraging differed between the two subcolonies, with both spatial (δ13C) and trophic-level (δ15N) differences involved. Thus, our study demonstrates the existence of foraging asymmetries in a pelagic seabird at a small spatial scale (between subcolonies), complementing patterns found at larger scales (between colonies). Moreover, the foraging asymmetries were associated with inequalities in fitness measures. We conclude that small-scale processes—in this case, systematic differences in the foraging ecology of local groups—can interact with large-scale oceanographic processes to determine seabird breeding success. Variation sous-coloniale du succès de reproduction de Fratercula cirrhata: Association avec l'écologie de la quête alimentaire et implications

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The migratory behaviour of narwhals (Monodon monoceros)

Canadian Journal of Zoology ◽

10.1139/z03-117 ◽

2003 ◽

Vol 81 (8) ◽

pp. 1298-1305 ◽

Cited By ~ 51

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.

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Stable Isotope Analysis Enhances Our Understanding of Diamondback Terrapin (Malaclemys terrapin) Foraging Ecology

Estuaries and Coasts ◽

10.1007/s12237-018-0476-6 ◽

2018 ◽

Vol 42 (2) ◽

pp. 596-611 ◽

Cited By ~ 1

Author(s):

Mathew J. Denton ◽

Amanda W. J. Demopoulos ◽

John D. Baldwin ◽

Brian J. Smith ◽

Kristen M. Hart

Keyword(s):

Stable Isotope ◽

Stable Isotope Analysis ◽

Foraging Ecology ◽

Isotope Analysis ◽

Diamondback Terrapin ◽

Malaclemys Terrapin

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Dive form and function in belugas Delphinapterus leucas of the eastern Canadian High Arctic

Polar Biology ◽

10.1007/s003000050299 ◽

1998 ◽

Vol 20 (3) ◽

pp. 218-228 ◽

Cited By ~ 25

Author(s):

A. R. Martin ◽

T. G. Smith ◽

O. P. Cox

Keyword(s):

High Arctic ◽

Delphinapterus Leucas ◽

Canadian High Arctic ◽

Form And Function ◽

And Function

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

10.22541/au.160682236.63502812/v1 ◽

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.

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