Giardia duodenalis and Cryptosporidium Spp. in the Intestinal Contents of Ringed Seals (Phoca hispida) and Bearded Seals (Erignathus barbatus) in Nunavik, Quebec, Canada

We flew a medium-altitude, systematic, strip-transect survey for ringed (Phoca hispida) and bearded seals (Erignathus barbatus) over western Hudson Bay in early June 1994 and 1995. The mean density (per square kilometre) of ringed seals hauled out on the ice was four times higher in 1995 (1.690) than in 1994 (0.380). The 1994 survey appeared to underestimate seal abundance because it was flown too late. Ringed seals preferred high ice cover habitat (6 + /8 ice) and, within this habitat, favoured cracking ice and large floes. We found no consistent effect of either wind or cloud cover on habitat preference. We estimated a total of 1980 bearded seals and 140<|>880 ringed seals hauled out on the sea ice in June 1995. A recent review of the relationship between ringed seal and polar bear (Ursus maritimus) populations suggests that a visible population of this size should support a population of up to 1300 polar bears, which is in general agreement with the current estimate of 1250-1300 bears in western Hudson Bay.

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Distribution and Abundance of Seals in the Eastern Beaufort Sea

Journal of the Fisheries Research Board of Canada ◽

10.1139/f77-150 ◽

1977 ◽

Vol 34 (7) ◽

pp. 976-988 ◽

Cited By ~ 50

Author(s):

Ian Stirling ◽

W. Ralph Archibald ◽

Douglas DeMaster

Keyword(s):

Marine Ecosystem ◽

Major Change ◽

Beaufort Sea ◽

Phoca Hispida ◽

Ringed Seals ◽

Erignathus Barbatus ◽

Independent Observations ◽

Baseline Information ◽

Reproductive Rates ◽

Bearded Seals

The objectives of this study were: (1) to design a statistically reliable method for surveying ringed seals (Phoca hispida) and bearded seals (Erignathus barbatus) that could be repeated and, (2) to obtain baseline information on the distribution, abundance, and general biology of ringed and bearded seals in relation to other mammals in the pack-ice ecosystem of the eastern Beaufort Sea.Because of the limitations encountered in aerial surveying during the period of optimum haul out, and the heterogeneous environment, we employed a stratified design incorporating a weighted linear regression model. Identical surveys, conducted from June 15 to 29, 1974 and from June 12 to 20, 1975, showed a significant decline in numbers of both seal species in 1975. This conclusion was supported by other independent observations. Observer bias in sighting and identifying the species of seals was tested for and rejected. Neither species was distributed randomly over the heterogeneous habitat but the degree of clumping was different. In general, bearded seals preferred shallower areas and ringed seals deeper ones.When the seal population declined, the reproductive rates of both species dropped markedly and young of the year virtually disappeared from the population. The reduction in numbers of seals stimulated a major change in reproductive rates of the polar bears (Ursus maritimus) and arctic foxes (Alopex lagopus) that depend upon them for food, and the bear and fox populations decreased in size.Some possible causes of the decline are discussed. This unprecedented variability in the stability of the marine ecosystem has serious management implications. Key words: census techniques, Phoca hispida, Erignathus barbatus, seals, interspecific relationships, Beaufort Sea

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The Distribution and Abundance of Seals in the Canadian High Arctic, 1980–82

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f85-147 ◽

1985 ◽

Vol 42 (6) ◽

pp. 1189-1210 ◽

Cited By ~ 75

Author(s):

M. C. S. Kingsley ◽

I. Stirling ◽

W. Calvert

Keyword(s):

Deep Water ◽

High Arctic ◽

Phoca Hispida ◽

Canadian High Arctic ◽

Ringed Seals ◽

Preferred Habitat ◽

Erignathus Barbatus ◽

Sverdrup Basin ◽

Amundsen Gulf ◽

Bearded Seals

Surveys of hauled-out ringed seals (Phoca hispida) and bearded seals (Erignathus barbatus) were flown in 1980 and 1981 over Jones Sound, the Sverdrup Basin, the channels between the Parry Islands, the Parry Channel, Prince of Wales Strait, and northern Amundsen Gulf. Part of the survey was flown again in 1982. Ringed seals were most numerous in Barrow Strait and Wellington Channel, their density decreasing westward and northward. Their preferred habitat was annual ice, fast or cracking, of high cover; they avoided deep water. Bearded seals were seen in low numbers in early-opening areas, preferring floe or rotten ice of moderate or low cover over shallow water.

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Aspects of Predation of Seals by Polar Bears

Journal of the Fisheries Research Board of Canada ◽

10.1139/f77-169 ◽

1977 ◽

Vol 34 (8) ◽

pp. 1126-1129 ◽

Cited By ~ 156

Author(s):

Ian Stirling ◽

W. Ralph Archibald

Keyword(s):

High Arctic ◽

Ursus Maritimus ◽

Polar Bears ◽

Phoca Hispida ◽

Ringed Seals ◽

Arctic Foxes ◽

Large Numbers ◽

Erignathus Barbatus ◽

Western Arctic ◽

Bearded Seals

Data were collected from 227 ringed seals (Phoca hispida) and bearded seals (Erignathus barbatus) killed by polar bears (Ursus maritimus) in the western arctic and the eastern high arctic. During periods of high ringed seal productivity, pups constituted at least half of the seals killed in both areas during the spring. Bearded seals were taken less often than ringed seals in both areas but were more important as prey to polar bears in the western arctic. Carcass utilization was significantly higher in the eastern high arctic than in the western arctic although the reason was not apparent. Scavenging of unutilized seal remains is probably of great importance to the survival of large numbers of arctic foxes (Alopex lagopus) through the winter. Key words: Ursus maritimus, Phoca hispida, Erignathus barbatus, predation, interspecific relationships, Arctic Ocean mammals

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Haul-out behaviour of ringed and bearded seals in relation to defence against surface predators

Canadian Journal of Zoology ◽

10.1139/z91-257 ◽

1991 ◽

Vol 69 (7) ◽

pp. 1857-1861 ◽

Cited By ~ 10

Author(s):

Michael C. S. Kingsley ◽

I. Stirling

Keyword(s):

Ursus Maritimus ◽

Ringed Seal ◽

Antipredator Behaviour ◽

Phoca Hispida ◽

Bearded Seal ◽

Ringed Seals ◽

Pack Ice ◽

Erignathus Barbatus ◽

Fast Ice ◽

Ice Floes

The ringed seal, Phoca hispida, hauls out at the edge of self-maintained breathing holes or narrow cracks, either in fast ice or in the centre of large floes in pack ice, apparently because this reduces its vulnerability to capture by polar bears, Ursus maritimus. Antipredator behaviour of ringed seals at haul-out sites also includes lying facing both their breathing hole and downwind, and vigilance. The much larger bearded seal, Erignathus barbatus, hauls out on the edges of wide leads or large holes in the ice, or on the points of small ice floes, and also faces both the water and downwind. Ice-associated seals which are not threatened by surface predators do not show these behaviour patterns.

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Haul-out behaviour and densities of ringed seals (Phoca hispida) in the Barrow Strait area, N.W.T.

Canadian Journal of Zoology ◽

10.1139/z79-263 ◽

1979 ◽

Vol 57 (10) ◽

pp. 1985-1997 ◽

Cited By ~ 35

Author(s):

Kerwin J. Finley

Keyword(s):

Wind Speed ◽

Early Morning ◽

Maximum Density ◽

Stable Population ◽

The Sun ◽

High Wind ◽

Phoca Hispida ◽

High Wind Speed ◽

Ringed Seals ◽

Calm Weather

Numbers of ringed seals hauled out on the ice began to increase in early June. Numbers on the ice were highest from 0900 to 1500 hours Central Standard Time and lowest (average 40–50% of peak) in early morning. Seals commonly remained on the ice for several hours, and occasionally (during calm weather) for > 48 h. Numbers on the ice were reduced on windy days and possibly also on unusually warm, bright and calm days. Seals tended to face away from the wind (particularly with high wind speed) and oriented broadside to the sun. Seals usually occurred singly (60–70% of all groups) at their holes.Numbers of seals hauled out at Freemans Cove remained relatively constant during June (maximum density 4.86/km2), whereas at Aston Bay numbers increased dramatically to a maximum density of 10.44/km2 in late June. The increase was thought to be due to an influx of seals abandoning unstable ice. The density of seal holes at Freemans Cove (5.92/km2) was much higher than at Aston Bay (2.73/km2). The ratio of holes to the maximum numbers of seals (1.12:1) at Freemans Cove represents a first estimate of this relationship in an apparently stable population.

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The scent of rutting male ringed seals(Phoca hispida)

Journal of Zoology ◽

10.1111/j.1469-7998.1992.tb07509.x ◽

1992 ◽

Vol 226 (4) ◽

pp. 681-689 ◽

Cited By ~ 19

Author(s):

M. Ryg ◽

Y. Solberg ◽

C. Lydersen ◽

T. G. Smith

Keyword(s):

Phoca Hispida ◽

Ringed Seals

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Bearded seal (Erignathus barbatus) vocalizations across seasons and habitat types in Svalbard, Norway

Polar Biology ◽

10.1007/s00300-021-02874-9 ◽

2021 ◽

Author(s):

Samuel M. Llobet ◽

Heidi Ahonen ◽

Christian Lydersen ◽

Jørgen Berge ◽

Rolf Ims ◽

...

Keyword(s):

Sea Ice ◽

Generalized Additive Models ◽

Extended Period ◽

Ice Cover ◽

High Arctic ◽

Additive Models ◽

Breeding Habitat ◽

Breeding Populations ◽

Erignathus Barbatus ◽

Bearded Seals

AbstractMale bearded seals (Erignathus barbatus) use vocal displays to attract females and to compete with other males during the mating season. This makes it possible to monitor breeding populations of this species using passive acoustic monitoring (PAM). This study analysed year-round acoustic data records from AURAL instruments in Svalbard (Norway) to investigate seasonal variation in the acoustic presence of male bearded seals and the phenology of different call types (long, step and sweep trills) at three sites representing a variety of habitats with varied ice conditions. Male bearded seals vocalized for an extended period at a drift-ice site (Atwain; January–July) north of Spitsbergen, while the vocal season was shorter at a High Arctic land-fast-ice site (Rijpfjorden; February–June) and shorter yet again at a west-coast site that has undergone dramatic reductions in sea ice cover over the last 1.5 decades (Kongsfjorden; April–June). Generalized Additive Models showed marked seasonal segregation in the use of different trill types at Atwain, where call rates reached 400 per h, with long trills being the most numerous call type. Modest segregation of trill types was seen at Rijpfjorden, where call rates reached 300 per h, and no segregation occurred in Kongsfjorden (peak call rate 80 per h). Sea ice cover was available throughout the vocal season at Atwain and Rijpfjorden, while at Kongsfjorden peak vocal activity (May–June) occurred after the sea ice disappeared. Ongoing climate warming and sea ice reductions will likely increase the incidence of such mismatches and reduce breeding habitat for bearded seals.

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