Variation in body size of ringed seals (Pusa hispida hispida) across the circumpolar Arctic: evidence of morphs, ecotypes or simply extreme plasticity?

The ringed seal is a small phocid seal that has a northern circumpolar distribution. It has long been recognized that body size is variable in ringed seals, and it has been suggested that ecotypes that differ in size exist. This study explores patterns of body size (length and girth) and age-at-maturity across most of the Arctic subspecies’ range using morphometric data from 35 sites. Asymptotic lengths varied from 113 to 151 cm, with sites falling into five distinct size clusters (for each sex). Age-at-maturity ranged from 3.1 to 7.4 years, with sites that had early ages of sexual maturity generally having small length-at-maturity and small final body length. The sexes differed in length at some sites, but not in a consistent pattern of dimorphism. The largest ringed seals occurred in western Greenland and eastern Canada, and the smallest occurred in Alaska and the White Sea. Latitudinal trends occurred only within sites in the eastern Canadian Arctic. Girth (with length and season accounted for) was also highly variable but showed no notable spatial pattern; males tended to be more rotund than females. Genetic studies are needed, starting with the “giants” at Kangia (Greenland) and in northern Canada to determine whether they are genetically distinct ecotypes. Additional research is also needed to understand the ecological linkages that drive the significant regional size differences in ringed seals that were confirmed in this study, and also to understand their implications with respect to potential adaptation to climate change.

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Anophryocephalus inuitorum sp.nov. and A. arcticensis sp.nov. (Eucestoda: Tetrabothriidae) in ringed seals (Phoca hispida hispida) and harp seals (Phoca groenlandica) from high-latitude seas of eastern Canada and the Arctic basin

Canadian Journal of Zoology ◽

10.1139/z95-005 ◽

1995 ◽

Vol 73 (1) ◽

pp. 34-44 ◽

Cited By ~ 2

Author(s):

Eric P. Hoberg ◽

Lena N. Measures

Keyword(s):

High Latitude ◽

Genital Atrium ◽

Canadian Arctic ◽

Arctic Basin ◽

The Arctic ◽

Phoca Hispida ◽

Eastern Canada ◽

Ringed Seals ◽

Phoca Groenlandica ◽

Eastern Canadian Arctic

Anophryocephalus inuitorum sp.nov. and A. arcticensis sp.nov. are described from ringed seals (Phoca hispida hispida) in the eastern Canadian Arctic; the latter species is also reported from harp seals (Phoca groenlandica) in the Gulf of St. Lawrence. Anophryocephalus inuitorum is most similar to A. skrjabini, but can be distinguished by fewer testes (14–27) and smaller dimensions of the strobila, neck (3.0–5.9 mm long), and cirrus sac (31–70 μm long), diameter of the genital atrium (44–68 μm), and length of the male canal (23–42 μm long). Anophryocephalus arcticensis resembles A. nunivakensis in the structure of the scolex, but is readily distinguished by a longer neck (8.9–14.7 mm), an elongate cirrus sac (60–98 × 44–73 μm) with a substantially thicker muscular wall, a more globular vitelline gland, and larger embryophores (29–41 μm long) and oncospheres (24–34 μm long). These are the first species of Anophryocephalus to be described from phocines in the eastern Canadian Arctic, and are included in a revised key for the genus.

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Growth and population parameters of ringed seals (Pusa hispida) from Svalbard, Norway, 2002–2004

ICES Journal of Marine Science ◽

10.1016/j.icesjms.2006.04.001 ◽

2006 ◽

Vol 63 (6) ◽

pp. 1136-1144 ◽

Cited By ~ 25

Author(s):

Bjørn A. Krafft ◽

Kit M. Kovacs ◽

Anne Kirstine Frie ◽

Tore Haug ◽

Christian Lydersen

Keyword(s):

Ringed Seal ◽

The Arctic ◽

Strong Impact ◽

Climate Change Scenarios ◽

Population Parameters ◽

Ringed Seals ◽

Asymptotic Values ◽

Seal Population ◽

Pusa Hispida ◽

Sexually Mature

AbstractSamples were collected in Svalbard, Norway, during April and May 2002–2004 from 272 ringed seals (Pusa hispida; 62.5% males, 37.5% females) to study growth and population parameters. The age of the animals ranged from 1 to 32 years. Asymptotic values for standard length and body mass were 127.7 ± 1.6 (s.e.) cm and 69.0 ± 2.7 kg for males (maxima: 144 cm and 92 kg) and 127.6 ± 2.3 cm and 68.9 ± 2.5 kg for females (maxima: 141 cm and 91 kg). All animals were sexually mature at an age ≥6 years and the ovulation rate was 0.86. Mean Age at Maturity (MAM) was 4.2 ± 0.2 years for males and 3.5 ± 0.3 years for females, values significantly lower than calculated for ringed seals from the same area 20 years ago. This change in MAM suggests that either the prey base for ringed seals in the area has increased or alternatively that the density of ringed seals has declined, such that more resources are available per capita. If the climate of the Arctic changes in the manner predicted by a host of climate-change scenarios, it is likely to have a strong impact on ringed seal populations in future, although there are no data to suggest that dramatic changes have taken place yet in fish and invertebrate populations in the Svalbard area. Although cause-and-effect cannot be firmly established, there is a possibility that the substantial increase in the number of polar bears (Ursus maritimus) over the past 20 years, since hunting the species in Svalbard ceased in 1973, may have played a role in the observed change in the ringed seal population.

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Circumpolar Trends of PCBs and Organochlorine Pesticides in the Arctic Marine Environment Inferred from Levels in Ringed Seals

Environmental Science & Technology ◽

10.1021/es991245i ◽

2000 ◽

Vol 34 (12) ◽

pp. 2431-2438 ◽

Cited By ~ 76

Author(s):

Derek Muir ◽

Frank Riget ◽

Marianne Cleemann ◽

Janneche Skaare ◽

Lars Kleivane ◽

...

Keyword(s):

Organochlorine Pesticides ◽

Marine Environment ◽

The Arctic ◽

Ringed Seals

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Stable ringed seal (Pusa hispida) demography despite significant habitat change in Svalbard, Norway

Polar Research ◽

10.33265/polar.v40.5391 ◽

2021 ◽

Vol 40 ◽

Author(s):

Magnus Andersen ◽

Kit M. Kovacs ◽

Christian Lydersen

Keyword(s):

Life History ◽

Sea Ice ◽

Close Association ◽

Ringed Seal ◽

Breeding Habitat ◽

Small Scale ◽

Recent Period ◽

Ringed Seals ◽

Time Periods ◽

Circumpolar Arctic

Ringed seals, which are small phocid seals, range across the circumpolar Arctic, and have evolved in close association with sea ice and depend on it for all aspects of their life history. This research study compares age structure, reproductive parameters, body size and condition during three time periods—1981–82 (n = 277), 2002–04 (n = 272) and 2012–18 (n = 212)—to study potential changes in demography in ringed seals in western Svalbard, Norway, an area that has undergone dramatic changes in sea-ice conditions during recent decades. Age distributions for the three time periods were similar, with the exception that the most recent period had a higher proportion of young animals. Age at sexual maturity for both sexes was similar for the two most recent periods, both being lower than in the 1980s. Ovulation rates did not vary significantly among the three periods (range 0.86–0.94). Pregnancy rates were only available for the most recent study period (0.71); this value falls within the range reported from other Arctic regions. Body length showed no clear temporal patterns; males were slightly longer in the most recent period, while females were slightly longer in the first period. Data from May in all periods suggest that body condition has not varied significantly through time. In conclusion, although the ringed seal breeding habitat in Svalbard has declined significantly in recent decades, demographic parameters appear to be largely unaffected. Life-history plasticity in combination with a small-scale regional variation in environmental conditions might explain the lack of changes in demography over time.

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Seasonal habitat use of a lagoon by ringed seals Pusa hispida in Svalbard, Norway

Marine Ecology Progress Series ◽

10.3354/meps13822 ◽

2021 ◽

Author(s):

J Vacquié-Garcia ◽

C Lydersen ◽

E Lydersen ◽

GN Christensen ◽

C Guinet ◽

...

Keyword(s):

Habitat Use ◽

Ringed Seals ◽

Pusa Hispida ◽

Seasonal Habitat Use

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Territorial Behavior of Short-eared Owls, Asio flammeus, at more than 1000 km North of their Current Breeding Range in Northeastern Canada: Evidence of Range Expansion?

The Canadian Field-Naturalist ◽

10.22621/cfn.v124i1.1032 ◽

2010 ◽

Vol 124 (1) ◽

pp. 58

Author(s):

Jean-François Therrien

Keyword(s):

Climate Change ◽

Range Expansion ◽

Territorial Behavior ◽

The Arctic ◽

Eastern Canada ◽

Breeding Range ◽

North Eastern ◽

Asio Flammeus

A pair of Short-eared Owls was observed throughout the summer of 2008 showing territorial behavior more than 1000 km north of their known breeding range in north-eastern Canada. These observations might be related to high lemming densities and/or climate change occurring in the Arctic.

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The role of thermal environment in determining the life history of a terrestrial salamander

Canadian Journal of Zoology ◽

10.1139/z00-116 ◽

2000 ◽

Vol 78 (10) ◽

pp. 1702-1711 ◽

Cited By ~ 7

Author(s):

Carlos D Camp ◽

Jeremy L Marshall

Keyword(s):

Body Size ◽

Thermal Environment ◽

Negative Relationship ◽

Size Variation ◽

Published Data ◽

Size At Maturity ◽

Adult Males ◽

Age At Maturity ◽

Adult Body Size ◽

Adult Body

Largely using previously published data, we analyzed geographic variation in adult body size of terrestrial salamanders of the Plethodon glutinosus complex. Maximum body size of adult males is determined by size at maturity. In turn, size at maturity is determined by a negative relationship with environmental temperature. Moreover, both age at maturity and growth rate are correlated with size at maturity, but apparently only as coincidental correlates through the influence of temperature. The number of degree-days, estimated using temperature data from respective geographic locations, accurately predicts age at maturity for salamanders living in these areas. Development under cooler thermal regimes is more depressed than growth and, consequentially, adult body sizes are greater in cooler climates. This pattern of size variation fits thermal predictive models proposed for larval development in amphibians that breed in ponds. Phenotypic variation in adult body size appears to be accounted for largely by plastic responses to variation in thermal environments and may reflect a single reaction norm for the complex.

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Four millennia of woodland structure and dynamics at the Arctic treeline of eastern Canada

Ecology ◽

10.1890/08-2317.1 ◽

2010 ◽

Vol 91 (5) ◽

pp. 1367-1379 ◽

Cited By ~ 17

Author(s):

Sarah Auger ◽

Serge Payette

Keyword(s):

The Arctic ◽

Eastern Canada ◽

Structure And Dynamics ◽

Arctic Treeline

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Late Quaternary sedimentation in Baffin Bay

Canadian Journal of Earth Sciences ◽

10.1139/e87-174 ◽

1987 ◽

Vol 24 (9) ◽

pp. 1833-1846 ◽

Cited By ~ 51

Author(s):

A. E. Aksu ◽

David J. W. Piper

Keyword(s):

Debris Flow ◽

Late Quaternary ◽

Ocean Basin ◽

The Arctic ◽

Bottom Current ◽

Eastern Canada ◽

Baffin Bay ◽

Quaternary Glaciation ◽

Continental Slopes ◽

Channel Systems

Baffin Bay is a small ocean basin that connects the Arctic and Atlantic oceans. The adjacent continental shelves have been extensively reworked during Quaternary glaciation. The shelf break generally lies between 200 and 500 m. The continental slope passes directly into the abyssal plain of Baffin Bay basin without any major submarine canyon – deep-sea fan system being present, except for a large smooth sediment apron in northern Baffin Bay.On the basis of over 50 piston cores, six Quaternary sediment facies are distinguished from detrital mineralogy (reflected in colour) and sediment texture. Facies A, B, and C are predominantly ice-rafted or are debris flow deposits, each with a distinct mineralogy. Facies D is turbidites and bottom-current sorted sands, silts, and muds. Facies E is hemipelagic sediment. Facies F consists of sediments ranging from slumps, through debris flow deposits, to fine-grained turbidites, with a distinctive provenance in northern Baffin Bay.These sediment facies appear to be partly controlled by glacial conditions. Hemipelagic facies E predominates during the present interglacial. During glacial stages, facies D turbidites were deposited. They resulted from slumping of proglacial sediments on the continental slopes off Greenland and Baffin Island. Facies C and F occurred on the continental slopes at these times. Ice-rafted facies A and B predominate at several horizons, reflecting a rapid breakup of ice shelves in northern Baffin Bay and increased rates of iceberg melting within the Bay. Overall sedimentation rates are relatively low, reflecting dry-base ice sheets in source areas.Deep-sea channel systems floored by sorted coarse sediments and bounded by muddy levees are absent in Baffin Bay, in contrast to mid-latitude glaciated continental margins off eastern Canada. These channel systems are the result of melting of wet-base glaciers, which provide a localized supply of sediment that is sorted by ice margin processes. In Baffin Bay, most glacial sediments are derived by calving of icebergs, probably from dry-base glaciers. Sediments are gradually released over large areas as the bergs melt, and are subsequently redistributed by debris flows.

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