scholarly journals Abundance of ringed seals (Phoca hispida) in the Kong Oscars Fjord, Scoresby Sund and adjacent areas in eastern Greenland

1998 ◽  
Vol 1 ◽  
pp. 152 ◽  
Author(s):  
E W Born ◽  
J Teilmann ◽  
F Riget
Keyword(s):  
Phoca Hispida ◽  
Ringed Seals ◽  
Point Estimates ◽  
Visible Part ◽  
Main Emphasis ◽  
Fast Ice ◽  
The Mean ◽  
Marine Productivity ◽  
One Year ◽  
Survey Effort

With the purpose of determining the distribution and abundance of ringed seals (Phoca hispida) hauling out on the ice, systematic strip census aerial surveys were flown in the Kong Oscars Fjord, Scoresby Sund and adjacent areas (between approximately 70°N and 72°30'N in eastern Greenland) from 7 to 13 June 1984. The study area comprised approximately 18,500 km2 mainly covered with smooth one-year-old shore-fast ice. The survey effort was concentrated in the afternoon during the presumed peak haul-out period. Main emphasis was given to surveying the Kong Oscars Fjord/Davy Sund and the Scoresby Sund/Hurry Fjord areas which were surveyed twice. Average densities in various sub-areas varied between 0.3 and 2.9 seals/km2 and were similar tothose reported from other Arctic areas. No significant differences in densities were found between sets of surveys of the same sub-areas. The mean density (2.00 seals/km2, SD=0.22) in the Scoresby Sund area was significantly higher than that found in Kong Oscars Fjord (1.04 seals/km\ SD=0.15) probably reflecting a higher overall marine productivity in Scoresby Sund. The sum of the point estimates of the visible part of the population in the different sub-areas was 28,882 seals.

Distribution and abundance of ringed (Phoca hispida) and bearded seals (Erignathus barbatus) in western Hudson Bay

1997 ◽  
Vol 54 (4) ◽  
pp. 914-921 ◽  
Author(s):  
N J Lunn ◽  
I Stirling ◽  
S N Nowicki
Keyword(s):  
Polar Bear ◽  
Hudson Bay ◽  
Phoca Hispida ◽  
Current Estimate ◽  
Ringed Seals ◽  
Erignathus Barbatus ◽  
The Mean ◽  
Western Hudson Bay ◽  
The Relationship ◽  
Bearded Seals

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.

Population parameters of ringed seals (Phoca hispida Schreber, 1775) in the Svalbard area

1987 ◽  
Vol 65 (4) ◽  
pp. 1021-1027 ◽  
Author(s):  
Christian Lydersen ◽  
Ian Gjertz
Keyword(s):  
Sex Ratio ◽  
Ringed Seal ◽  
Adult Males ◽  
Population Parameters ◽  
Phoca Hispida ◽  
Age Class ◽  
Ringed Seals ◽  
Males And Females ◽  
The Mean ◽  
Sexually Mature

Samples were taken from 284 ringed seals (Phoca hispida) in the Svalbard area during April–July 1981 and March–April 1982. The age of 283 seals was determined by reading annuli in the cementum of the canine teeth. The mean age of the males was 11.3 years, and of the females, 14.9 years. Females were found to be significantly older than males. The mean length of sexually mature ringed seals was 128.9 cm for both sexes. The mean weight of adult males and females was 53.5 and 61.4 kg, respectively. Females were found to be significantly heavier than males. The sex ratio was 47.8% males and 52.2% females. Studies of microscopic sections of testis and epididymis from ringed seal males showed that 63, 75, and 80% of 5-, 6-, and 7-year-old animals, respectively, were sexually mature. The weights of testis and epididymis, diameters of tubuli, and the size of testis all showed a marked increase in the 5-year age-class. Macroscopic sections of ovaries from ringed seal females showed that 20, 60, and 80% of 3-, 4-, and 5-year-old animals, respectively, were sexually mature. The size of the ovaries showed a marked increase in the 5-year age-class. The ovulation rate of ringed seals from Svalbard was calculated to be 0.91.

Characteristics of ringed seal, Phoca hispida, subnivean structures and breeding habitat and their effects on predation

1996 ◽  
Vol 74 (5) ◽  
pp. 858-874 ◽  
Author(s):  
C. M. Furgal ◽  
K. M. Kovacs ◽  
S. Innes
Keyword(s):  
Snow Depth ◽  
Function Analysis ◽  
Ringed Seal ◽  
Breeding Habitat ◽  
Phoca Hispida ◽  
Ringed Seals ◽  
Arctic Foxes ◽  
Ridge Height ◽  
Length Width ◽  
Fast Ice

Characteristics of ringed seal (Phoca hispida) subnivean structures and breeding habitat were quantified and their potential influence on predation success by polar bears (Ursus maritimus), arctic foxes (Alopex lagopus), and humans on ringed seals was investigated in Admiralty Inlet and Strathcona Sound, Northwest Territories. A total of 237 ringed seal structures were located between April and June 1991–1993 using trained dogs. Ringed seal lairs and breathing holes were concentrated in areas of deep snow, and were associated with large, thick ice ridges. Only a small percentage of the available fast-ice habitat had sufficient snow depth for lair construction each year. A discriminant function analysis used to classify structures located in 1992, using a combination of structural and habitat measurements, correctly classified 70% of structures located in 1991 and 1993 into functional groups. The length, width, internal height, and level of "tiggak," the odour of rutting male ringed seals, associated with structures were the most important descriptors separating structure types. Seventy-three percent of structures located in the study were undisturbed by predators. The mean length and width of structures entered by predators were significantly greater than those of undisturbed structures. Polar bear success decreased as snow depth and the thickness of the roof covering the structures increased. The conditions necessary for successful arctic fox predation are unclear. Inuit hunters attacked structures close to ice ridges, and ridge height and snow depth influenced their success. All predators attacked lairs having the odour of rutting male ringed seals less often than structures with no male odour.

Midsummer observations on the behavior of wild polar bears (Ursus maritimus)

1974 ◽  
Vol 52 (9) ◽  
pp. 1191-1198 ◽  
Author(s):  
Ian Stirling
Keyword(s):  
Diurnal Rhythm ◽  
Intraspecific Competition ◽  
Ursus Maritimus ◽  
Polar Bears ◽  
Phoca Hispida ◽  
Devon Island ◽  
Adult Females ◽  
Ringed Seals ◽  
Single Animal ◽  
The Mean

Wild polar bears (Ursus maritimus) were observed from Caswall Tower, Devon Island (74°43′ N; 91°10′ W), from 24 July to 8 August 1973. A total of 602.7 bear hours of observations was recorded. Two types of hunting were observed, stalking and still-hunting. Of 288 hunts observed, 65 (22.6%) were stalks and 233 (77.4%) were still-hunts. All cubs observed hunted, but they exhibited great variety in patience and apparent skill. Scavenging and intraspecific competition for possession of kills were observed. When threatened, adult females with cubs were not subordinate to tears of any other age or sex classes. A diurnal rhythm was recorded in which bears slept most during the latter third of the 24-h cycle and least in the first third. The average of 17 sleeps longer than 60 min was 465 ± 301.3 min.Basking ringed seals (Phoca hispida) alternated between lying flat and raising their heads to look about for predators. The mean duration of the lying and looking phases was 26.3 and 7.0 s respectively (n = 591 and 580). The variation between individual seals was greater than within individuals. If a group of seals hauled out together, all individuals maintained watchful behavior; no single animal acted as a "sentry" for the others.

scholarly journals The ringed seal (Phoca hispida) in the western Russian Arctic

1998 ◽  
Vol 1 ◽  
pp. 63 ◽  
Author(s):  
Stanislav E Belikov ◽  
Andrei N Boltunov
Keyword(s):  
Barents Sea ◽  
White Sea ◽  
Ringed Seal ◽  
Kara Sea ◽  
Russian Arctic ◽  
The White Sea ◽  
Phoca Hispida ◽  
Ringed Seals ◽  
The Barents Sea ◽  
Fast Ice

This paper presents a review of available published and unpublished material on the ringed seal (Phoca hispida) in the western part of the Russian Arctic, including the White, Barents and Kara seas. The purpose of the review is to discuss the status of ringed seal stocks in relation to their primary habitat, the history of sealing, and a recent harvest of the species in the region. The known primary breeding habitats for this species are in the White Sea, the south-western part of the Barents Sea, and in the coastal waters of the Kara Sea, which are seasonally covered by shore-fast ice. The main sealing sites are situated in the same areas. Female ringed seals become mature by the age of 6, and males by the age of 7. In March-April a female gives birth to one pup in a breeding lair constructed in the shore-fast ice. The most important prey species for ringed seals in the western sector of the Russian Arctic are pelagic fish and crustaceans. The maximum annual sealing level for the region was registered in the first 70 years of the 20th century: the White Sea maximum (8,912 animals) was registered in 1912; the Barents Sea maximum (13,517 animals) was registered in 1962; the Kara Sea maximum (13,200 animals) was registered in 1933. Since the 1970s, the number of seals harvested has decreased considerably. There are no data available for the number of seals harvested annually by local residents for their subsistence.

Spatiotemporal use of lairs by ringed seals (Phoca hispida)

1990 ◽  
Vol 68 (12) ◽  
pp. 2503-2512 ◽  
Author(s):  
Brendan P. Kelly ◽  
Lori T. Quakenbush
Keyword(s):  
Early Spring ◽  
Late Spring ◽  
Phoca Hispida ◽  
Ringed Seals ◽  
Fast Ice ◽  
Males And Females

Thirteen ringed seals monitored by radiotelemetry in the shore-fast ice of the Beaufort and Chukchi seas were faithful to subnivean haulout sites from March to June. Each seal frequented as many as four lairs; the distances between lairs used by individual seals were as great as 3438 m. Mean distances between lairs used by individual males and females were 1997 and 634 m, respectively. Seals were not commonly seen resting on the ice outside of lairs until late May or June, but two radio-tagged male seals began basking on 15 April and 7 May, respectively. The proportion of time spent out of the water was 12.1% in March, 18.6% in April, 21.9% in May, and 42.9% in early June. From late March to June, males were out of the water during 13.1% of the monitored periods, and females were out of the water during 24.0% of those periods. Mean hours of haulout bouts were between 18:00 and 02:30 in early spring (except for a lactating female who hauled out most frequently at 11:00) and between 10:00 and 16:30 in late spring.

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

1991 ◽  
Vol 69 (7) ◽  
pp. 1857-1861 ◽  
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.

Use of artificial subice air pockets by wild ringed seals (Phoca hispida)

1974 ◽  
Vol 52 (8) ◽  
pp. 1092-1093 ◽  
Author(s):  
Allen R. Milne
Keyword(s):  
Sea Ice ◽  
Air Bubbles ◽  
Phoca Hispida ◽  
Scuba Divers ◽  
Ringed Seals ◽  
Naturally Occurring ◽  
Drainage Channels ◽  
Fast Ice ◽  
Air Pockets

Ringed seals were observed to inhale exhaust air expelled by SCUBA divers who were diving under 1.9-m thick, 1-year-old fast ice in Lancaster Sound during mid-April, 1973, The underside of the sea ice was imperfectly flat so that some of the bubbles of exhaust air coalesced into large lenticular bubbles 1 to 3 cm in depth, and these, on occasions, were partially inhaled by seals. Between dives, separated in time by as little as 3 h, all the under-ice air bubbles, large and small, vanished. It is assumed that the buoyant air migrated upward into the sea ice by the progressive displacement of brine in drainage channels. Although the exhaust air was readily used by ringed seals, it is unlikely that naturally occurring air pockets can persist beneath 1 -year-old sea ice to enable seals to extend their under-ice travels.

Comparison of Heavy Metals in Two Groups of Ringed Seals (Phoca hispida) from the Canadian Arctic

1989 ◽  
Vol 46 (9) ◽  
pp. 1558-1563 ◽  
Author(s):  
R. Wagemann
Keyword(s):  
Heavy Metals ◽  
Reference Group ◽  
Canadian Arctic ◽  
Phoca Hispida ◽  
Mine Area ◽  
Ringed Seals ◽  
Lead Zinc ◽  
Zinc Mine ◽  
The Mean ◽  
Positive Correlations

Heavy metals (Pb, Hg, Cd, Cu, and Zn) and Se and As were determined in liver, kidney, and muscle of ringed seals captured near a lead–zinc mine in the Strathcona Sound area, and in a reference group from Admiralty Inlet in the Canadian Arctic. The mean concentrations of Pb in liver and muscle and Se in muscle were higher in seals shot near the mine area than in a reference group shot 50–75 km from this area, notwithstanding large variances in metal concentrations arising from inter-metal and Hg–age and Cd–age positive correlations. Strong positive correlations were found between age of animals in the reference group and Cd in kidney and Hg in liver between Se and Hg in liver, and a negative one between age and Cu in the three tissues examined. Nearly halt of the individuals in the mine-area group were shown, by multiple linear regression, to have higher Hg, Pb, or Cd than the reference group. High Cd concentrations were found in tissues of seals from both groups.

scholarly journals Incomplete Kawasaki disease - a diagnostic and therapeutic challenge

2014 ◽  
Vol 9 (4) ◽  
pp. 30-35
Author(s):  
S Datta ◽  
S Maiti ◽  
G Das ◽  
A Chatterjee ◽  
P Ghosh
Keyword(s):  
Kawasaki Disease ◽  
Intravenous Immunoglobulin ◽  
Incomplete Kawasaki Disease ◽  
Duration Of Symptoms ◽  
Clinical Criteria ◽  
Echocardiographic Finding ◽  
2D Echocardiography ◽  
Acquired Heart Disease ◽  
The Mean ◽  
One Year

Background The diagnosis of classical Kawasaki Disease was based on clinical criteria. The conventional criteria is particularly useful in preventing over diagnosis, but at the same time it may result in failure to recognize the incomplete form of Kawasaki Disease. Objective To suspect incomplete Kawasaki Disease, because early diagnosis and proper treatment may reduce substantial risk of developing coronary artery abnormality which is one of the leading causes of acquired heart disease in children. Method Nine cases of incomplete Kawasaki Disease were diagnosed over a period of one year. The diagnosis of incomplete Kawasaki Disease was based on fever for five days with less than four classical clinical features and cardiac abnormality detected by 2D- echocardiography. A repeat echocardiography was done after 6 weeks of onset of illness. The patients were treated with Intravenous Immunoglobulin and/or aspirin. Result The mean age of the patients was 3.83 years and the mean duration of symptoms before diagnosis was 12.1 days. Apart from other criteria all of our patients had edema and extreme irritability. All the patients had abnormal echocardiographic finding. Five patients received only aspirin due to nonaffordability of Intravenous Immunoglobulin and four patients received both aspirin and Intravenous Immunoglobulin, but the outcome was excellent in all the cases. Conclusion Incomplete Kawasaki Disease can be diagnosed with more awareness and aspirin alone may be used as a second line therapy in case of non affordability of Intravenous Immunoglobulin. Journal of College of Medical Sciences-Nepal, 2013, Vol-9, No-4, 30-35 DOI: http://dx.doi.org/10.3126/jcmsn.v9i4.10234

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