An on-ice aerial survey of the Kane Basin polar bear (Ursus maritimus) subpopulation

AbstractThere is an imminent need to collect information on distribution and abundance of polar bears (Ursus maritimus) to understand how they are affected by the ongoing decrease in Arctic sea ice. The Kane Basin (KB) subpopulation is a group of high-latitude polar bears that ranges between High Arctic Canada and NW Greenland around and north of the North Water polynya (NOW). We conducted a line transect distance sampling aerial survey of KB polar bears during 28 April–12 May 2014. A total of 4160 linear kilometers were flown in a helicopter over fast ice in the fjords and over offshore pack ice between 76° 50′ and 80° N′. Using a mark-recapture distance sampling protocol, the estimated abundance was 190 bears (95% lognormal CI: 87–411; CV 39%). This estimate is likely negatively biased to an unknown degree because the offshore sectors of the NOW with much open water were not surveyed because of logistical and safety reasons. Our study demonstrated that aerial surveys may be a feasible method for obtaining abundance estimates for small subpopulations of polar bears.

Download Full-text

Observations of Arctic Sea Ice Leads and Open Water During the Microbiological-Ocean-Cloud Coupling in the High Arctic Campaign

IGARSS 2020 - 2020 IEEE International Geoscience and Remote Sensing Symposium ◽

10.1109/igarss39084.2020.9324103 ◽

2020 ◽

Author(s):

Son V. Nghiem ◽

Rachel M. Kirpes ◽

Jun Liu ◽

Kerri A. Pratt ◽

Patricia Matrai ◽

...

Keyword(s):

Sea Ice ◽

Open Water ◽

High Arctic ◽

Arctic Sea Ice ◽

Arctic Sea ◽

Ice Leads

Download Full-text

Applications of Satellite Thermal Infrared Images for Monitoring North Water during the Periods of Polar Darkness

Journal of Glaciology ◽

10.3189/s0022143000015276 ◽

1980 ◽

Vol 25 (93) ◽

pp. 425-438

Author(s):

B. Dey

Keyword(s):

Satellite Images ◽

Open Water ◽

Thermal Infrared ◽

Water Area ◽

Infrared Images ◽

Baffin Bay ◽

The North ◽

Thermal Infrared Images ◽

North Water

AbstractThe study reported here illustrates the unique value of NOAA thermal infrared (TIR) images for monitoring the North Water area in Smith Sound and northern Baffin Bay during the periods of polar darkness. Wintertime satellite images reveal that, during the months of December through February, open water and thin ice occur in a few leads and polynyas. However, in March, the areas of open water and thin ice decrease to a minimum with a consequent higher concentration of ice. Two ice dams, in northern Kennedy Channel and in northern Smith Sound, regulate the flow of ice into northern Baffin Bay and also determine the areal variations of open water and thin ice in Smith Sound.

Download Full-text

Living at a High Arctic Polynya: Inughuit Settlement and Subsistence around the North Water during the Thule Station Period, 1910–53

ARCTIC ◽

10.14430/arctic4573 ◽

2016 ◽

Vol 69 (5) ◽

pp. 1 ◽

Cited By ~ 6

Author(s):

Bjarne Grønnow

Keyword(s):

Raw Materials ◽

High Arctic ◽

Ringed Seal ◽

Site Location ◽

Ice Cap ◽

The North ◽

North Water Polynya ◽

Annual Range ◽

North Water ◽

The Rich

The settlement and subsistence patterns of the Inughuit of the Avanersuaq (Thule area) are described and analyzed for the years 1910 to 1953, when Knud Rasmussen’s trading station at Dundas was active. Inughuit subsistence was based on the rich biotic resources of the North Water polynya between Ellesmere Island and Greenland, but the analysis shows that trade, primarily with fox furs at the Thule Station, also played a major role in shaping the settlement pattern of the period. During the Thule Station Period, the named winter settlements amounted to c. 40 sites; however, only 10–15 of them were settled at any given time. The Inughuit settlement close to the station, Uummannaq, soon became the largest site in the area. The sources enable us to follow changes of residence of some hunting families over four decades. By moving their winter sites every second or third year, the families gained primary knowledge of the topography and seasonal variation of the hunting grounds in the entire Thule district during their active years. In the same way, they connected with diverse family networks through the years. Tracing the sledge routes that connected the sites over great distances reveals how decisive proximity to main and escape routes over the Ice Cap was for site location. Dog sledge technology, and thus capacity to transport people, gear, and stored food, boomed during the Thule Station Period with the wealth created from trade and access to raw materials. Mapping the main hunting grounds on the sea ice and modeling the hunters’ annual range of possibilities for accessing different game—mainly walrus, ringed seal, narwhal, and sea birds (plus some caribou)—showed that ringed seal formed the bread and butter of the subsistence economy. However, bulk resources, gained in particular from intensive spring walrus hunts at a few hot spots, as well as carefully timed consumption and sharing of the stored meat and blubber, were keys to life at the North Water polynya. Temporary settlement at the trading stations in the area—a couple of winters at a time—was also part of the risk management strategy of the Inughuit.

Download Full-text

Ice Conditions of an Arctic Polynya: North Water in Winter

Journal of Glaciology ◽

10.1017/s0022143000012089 ◽

1986 ◽

Vol 32 (112) ◽

pp. 383-390 ◽

Cited By ~ 35

Author(s):

Konrad Steffen

Keyword(s):

Sea Water ◽

Surface Condition ◽

Open Water ◽

Sea Surface ◽

Aerial Images ◽

The Arctic ◽

The North ◽

North Water ◽

Ice Conditions ◽

Fast Ice

AbstractThe surface condition of the North Water was investigated during two winters (i.e. the three polynyas: Smith Sound polynya, Lady Ann Strait polynya, and Barrow Strait polynya). Since no detailed information was available on ice conditions and the extent of open water during winter, radiometric temperature measurements of the sea surface had to be taken along a flight line of 2650 km from an altitude of 300 m. From November to March 1978-79 and 1980-81, 14 remote-sensing flights were carried out. On the basis of the radiometric measurements, the following ice types were identified: ice-free, dark nilas, light nilas, grey ice, grey-white ice, and white ice. A comparison between the thermal and the visual ice classification (the latter being based on grey tones of the aerial images) showed a deviation of 3%. The analysis showed that in November, December, and January more than 50% of the Smith Sound polynya was covered by young ice, nilas, and ice-free, whereas in February and March white ice was dominant. Moreover, it was found that the two polynyas in Smith Sound and Lady Ann Strait were much smaller than previously believed. In Barrow Strait, a semi-permanent polynya was observed in the winter of 1980-81. The occurrence of polynyas in Barrow Strait seems to be connected with the location of the fast-ice edge. On the basis of the calculated ice-type distribution and heat-flux rates for different ice types, an energy loss of 178 W m-2was found on the surface of the Smith Sound polynya due to open water and thin ice for the winter months November to March. Compared with other ice-covered sea surfaces in the Arctic, the heat release by the sea-water in the Smith Sound polynya is about 100 W m-2larger.

Download Full-text

Long-distance swimming by polar bears (Ursus maritimus) of the southern Beaufort Sea during years of extensive open water

Canadian Journal of Zoology ◽

10.1139/z2012-033 ◽

2012 ◽

Vol 90 (5) ◽

pp. 663-676 ◽

Cited By ~ 53

Author(s):

A.M. Pagano ◽

G.M. Durner ◽

S.C. Amstrup ◽

K.S. Simac ◽

G.S. York

Keyword(s):

Sea Ice ◽

Adult Female ◽

Open Water ◽

Ursus Maritimus ◽

Polar Bears ◽

Long Distance ◽

Gps Collars ◽

Movement Data ◽

Global Positioning ◽

Ice Conditions

Polar bears ( Ursus maritimus Phipps, 1774) depend on sea ice for catching marine mammal prey. Recent sea-ice declines have been linked to reductions in body condition, survival, and population size. Reduced foraging opportunity is hypothesized to be the primary cause of sea-ice-linked declines, but the costs of travel through a deteriorated sea-ice environment also may be a factor. We used movement data from 52 adult female polar bears wearing Global Positioning System (GPS) collars, including some with dependent young, to document long-distance swimming (>50 km) by polar bears in the southern Beaufort and Chukchi seas. During 6 years (2004–2009), we identified 50 long-distance swims by 20 bears. Swim duration and distance ranged from 0.7 to 9.7 days (mean = 3.4 days) and 53.7 to 687.1 km (mean = 154.2 km), respectively. Frequency of swimming appeared to increase over the course of the study. We show that adult female polar bears and their cubs are capable of swimming long distances during periods when extensive areas of open water are present. However, long-distance swimming appears to have higher energetic demands than moving over sea ice. Our observations suggest long-distance swimming is a behavioral response to declining summer sea-ice conditions.

Download Full-text

Aerial line transect survey to estimate abundance of marsh deer (Blastocerus dichotomus) (Illiger, 1815)

Brazilian Archives of Biology and Technology ◽

10.1590/s1516-89132005000600017 ◽

2005 ◽

Vol 48 (5) ◽

pp. 807-814 ◽

Cited By ~ 9

Author(s):

Artur Andriolo ◽

Ubiratan Piovezan ◽

Mateus José Rodrigues Paranhos da Costa ◽

Jeff Laake ◽

José Maurício Barbanti Duarte

Keyword(s):

Population Size ◽

River Basin ◽

Distance Sampling ◽

Aerial Survey ◽

Line Transect ◽

Sampling Methodology ◽

Future Analysis ◽

Line Transect Survey ◽

Blastocerus Dichotomus ◽

The Impact

The objective was to estimate abundance of marsh deer in the Paraná River basin of this work. The results provided information to support further analysis of the impact of the Porto Primavera flooding lake over population. Sixty-nine animals were recorded by aerial survey using distance sampling methodology. Animals were widely distributed throughout the study area. The uncorrected data resulted in a estimate density of 0.0035 ind/ha and a population size of 636 individuals. Correcting the g for the animals that could be missed the calculated abundance was 896 (CV=0.27) individuals. This methodology was applied with success to survey marsh deer. The result was important to evaluate the marsh deer status in the area, and for future analysis of the impact of the flooding dam.

Download Full-text

High Arctic Polynyas in a Changing Climate

10.5194/egusphere-egu2020-17959 ◽

2020 ◽

Author(s):

Rebecca Jackson ◽

Anna Bang Kvorning ◽

Christof Pearce ◽

Marit-Solveig Seidenkrantz ◽

Sofia Ribeiro

Keyword(s):

Sea Ice ◽

Indigenous Communities ◽

High Arctic ◽

Arctic Sea Ice ◽

Holistic View ◽

The Holocene ◽

Changing Climate ◽

New Findings ◽

North Water ◽

Ice Conditions

Polynyas, areas of open water in the otherwise sea-ice dominated high Arctic, are vital oases for biological productivity, supporting a plethora of marine mammals and birds that in turn sustain indigenous communities. Polynyas are not, however, consistent features. Beyond the observational era, little to nothing is known about their past dynamics and equally, about their resilience to emerging changes in Arctic sea-ice conditions.Recent paleoceanographic reconstructions of the North Water in northern Baffin Bay, the largest of the high Arctic polynyas, indicate that the polynya contracted in response to warm climatic intervals during the Holocene (e.g. Roman Warm Period). In contrast, the onset of stable North Water polynya formation acted to suppress northward incursion of warm Atlantic-sourced waters. This highlighted not only the sensitivity of polynyas to past climatic changes, but the role their formation plays in mediating water column dynamics and ocean circulation.These new findings provided the rationale for the MSCA project &#8216;POLARC: High Arctic Polynyas in a Changing Climate&#8217;, to investigate the Holocene dynamics of other high Arctic polynyas forming off the east Greenland coast. New marine sedimentary archives and a multiproxy approach will be used to reconstruct productivity, sea-ice conditions and bottom water conditions, capturing a holistic view of these systems and their interaction with climatic and oceanographic variation during the Holocene (11,700 years BP to present). We present here preliminary paleoceanographic reconstructions of the Sirius Water, the first Holocene record from this polynya region, as well as plans for model-data comparisons in key polynya regions with the aim of constraining the past and better predicting the future of these phenomena.

Download Full-text