Winter Distribution of Ringed Seals (Phoca hispida) in the Barrow Strait Area, Northwest Territories, Determined by Underwater Vocalizations

1985 ◽  
Vol 42 (7) ◽  
pp. 1238-1243 ◽  
Author(s):  
Wendy Calvert ◽  
Ian Stirling
Keyword(s):  
Northwest Territories ◽  
Habitat Quality ◽  
Human Activity ◽  
High Arctic ◽  
Diel Cycle ◽  
Phoca Hispida ◽  
Winter Distribution ◽  
Ringed Seals ◽  
Habitat Variables

In order to assess underice distribution of ringed seals (Phoca hispida) in winter, we made recordings from 23 to 30 April 1982 at 32 sites chosen to represent different habitats in the High Arctic. By regressing the vocalization rate at each site against variables for habitat quality, we found that sites in smooth interisland channels had significantly more vocalizations than sites in bays, and sites with frequent human activity had vocalization rates similar to the overall average. Although differences in vocalization rates correlated with some measured and estimated habitat variables, there was too much overlap between sites for vocalization rate alone to be useful in separating suitable and unsuitable pupping habitat. Recordings made at one site over 4 d showed a diel cycle in which vocalization rate was highest from about 08:30 to 16:30 and lowest at night.

Factors affecting the distribution and abundance of ringed seal structures in Barrow Strait, Northwest Territories

1989 ◽  
Vol 67 (9) ◽  
pp. 2212-2219 ◽  
Author(s):  
M. O. Hammill ◽  
T. G. Smith
Keyword(s):  
Northwest Territories ◽  
Ringed Seal ◽  
Phoca Hispida ◽  
Factors Affecting ◽  
Habitat Features ◽  
Ringed Seals ◽  
Over The Top ◽  
The Relationship ◽  
Important Habitat ◽  
Habitat Variables

The relationship between the distribution of ringed seals, Phoca hispida, and habitat was examined in Barrow Strait, Northwest Territories. Density of seal breathing holes was used as an index of seal abundance. Birth lairs were associated with the largest snowdrifts. Lair formation can occur within 24 h after a snowdrift forms over the top of a breathing hole. Seal structures were associated with ridges consisting of ice pieces 15–25 cm thick projecting upwards to a height of 80–150 cm. In 1975 and 1986, the combination of date of ice consolidation and snow depth were the most important habitat features affecting the distribution of ringed seals structures. This was also true with respect to distribution of birth lairs and undefined haul-out lairs, but no relationship was identified between density of structures used by males and habitat. Snow cover and date of ice consolidation were not identified as important habitat variables in 1984 and 1985 when overall distribution of ice in Barrow Strait was very different. Birth lairs were not seen before 4 April, but were found in increasing frequency as the season progressed. Male structures were evident in late March, but were not found after mid-May.

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

1985 ◽  
Vol 42 (6) ◽  
pp. 1189-1210 ◽  
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.

Aspects of Predation of Seals by Polar Bears

1977 ◽  
Vol 34 (8) ◽  
pp. 1126-1129 ◽  
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

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

1979 ◽  
Vol 57 (10) ◽  
pp. 1985-1997 ◽  
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.

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.

The scent of rutting male ringed seals(Phoca hispida)

1992 ◽  
Vol 226 (4) ◽  
pp. 681-689 ◽  
Author(s):  
M. Ryg ◽  
Y. Solberg ◽  
C. Lydersen ◽  
T. G. Smith
Keyword(s):  
Phoca Hispida ◽  
Ringed Seals

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.

Biotransformation of PCBs in Relation to Phase I and II Xenobiotic-Metabolizing Enzyme Activities in Ringed Seals (Phoca hispida) from Svalbard and the Baltic Sea

2008 ◽  
Vol 42 (23) ◽  
pp. 8952-8958 ◽  
Author(s):  
Heli Routti ◽  
Robert J. Letcher ◽  
Augustine Arukwe ◽  
Bert van Bavel ◽  
Nigel G. Yoccoz ◽  
...  
Keyword(s):  
Phase I ◽  
Baltic Sea ◽  
Enzyme Activities ◽  
Phoca Hispida ◽  
The Baltic Sea ◽  
Ringed Seals ◽  
Metabolizing Enzyme ◽  
The Baltic ◽  
Phase I And Ii
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