Mass natural mortality of walruses (Odobenus rosmarus) at St. Lawrence Island, Bering Sea, autumn 1978
Arctic, v. 33, no. 2, June 1980, p. 226-245, ill., figures, photos., tables
ASTIS record 4520
In October-November 1978, several thousand living walruses came ashore in at least four localities on St. Lawrence Island where they had not been present before in this century. They hauled out also at two other sites which they have occupied annually but in much smaller numbers. At least 537 animals died on the haulout areas at that time, and approximately 400 other carcasses washed ashore from various sources. This was by far the greatest mortality of walruses ever recorded in an event of this kind. At least 15% of the carcasses on the haulouts were aborted fetuses, 24% were 5-6-month-old calves; the others were older animals ranging in age from 1 to 37 years old. About three-fourths of the latter on the haulouts were females; in the non-haulouts areas the sex ratio was about 1:1. Forty of the best preserved carcasses were examined by necropsy. The principal cause of death was identified as extreme torsion of the cervical spine, with resultant cerebrospinal hemorrhage, apparently due to traumatization by other walruses. Nearly all of the dead were extremely lean, having less than half as much subcutaneous fat as healthy animals examined in previous years.
Socioeconomic evaluation of reindeer herding in northwestern Alaska
Arctic, v. 33, no. 2, June 1980, p. 246-272, ill., figures, tables
ASTIS record 4521
Recent proposals to create new federal lands and management jurisdiction in Alaska, associated with the Alaska Native Claims Settlement Act (1971) and pending government legislation, have combined to bring this Native industry into prominence once again. Based on an interdisciplinary study undertaken from 1976 through 1977, contemporary herding is discussed, set against the background of history, the economic considerations and the unique Native culture and lifestyle. Reindeer herding has become an integral part of the social organization, value and cultural systems, as well as economy, of northwestern Alaska. Changes in the industry, whether to improve herding operations or as a result of government legislation, would greatly affect the people and economy of the region.
This account of the Canol's Mackenzie air fields is based on personal diaries and reflects the author's participation from the spring of 1942 to the summer of 1945.
Satellite images are a useful tool in the study of sea ice dynamics. The results of studies using satellite images of Mackenzie Bay during the break-up and freeze-up periods are presented in maps and tables. These indicate important temporal variations in the processes of bay ice break-up and freeze-up. Though the Mackenzie Bay break-up proceeds from the south and from the north, the southern melt rate is faster because of an influx of warm water from the Mackenzie River. The freeze-up proceeds from south to north, i.e., from the fresh water area to the saline water area of the bay. The study of Mackenzie Bay ice dynamics is important because of the barge traffic through the Mackenzie River and also because of offshore drilling activities in the Beaufort Sea.
In traditional Inuit society the availability of game resources must always have been one of the most important criteria for the determination of settlement locations. A number of ecological factors determine the availability of particular game species in the Arctic regions. The presence of open water areas known as polynyas is one of these factors. The relationship between polynya distributions and prehistoric settlement patterns in the High Arctic is explored, with particular reference to the Bache Peninsula region on the east coast of Ellesmere Island, N.W.T.
Polynyas are areas of open water surrounded by ice. In the Canadian Arctic, the largest and best-known polynya is the North Water. There are also several similar, but smaller, recurring polynyas and shore lead systems. Polynyas appear to be of critical importance to arctic marine birds and mammals for feeding, reproduction and migration. Despite their obvious biological importance, most polynya areas are threatened by extensive disturbance and possible pollution as a result of proposed offshore petrochemical exploration and year-round shipping with ice-breaking capability. However, we cannot evaluate what the effects of such disruptions might be because to date we have conducted insufficient research to enable us to have a quantitative understanding of the critical ecological processes and balances that may be unique to polynya areas. It is essential that we rectify the situation because the survival of viable populations or subpopulations of several species of arctic marine birds and mammals may depend on polynyas.
Atmospheric polycyclic aromatic hydrocarbons : an aspect of air pollution in Fairbanks, Alaska
Arctic, v. 33, no. 2, June 1980, p. 316-325, ill., tables
ASTIS record 4526
Quantitative analysis of atmospheric polycyclic aromatic hydrocarbons (PAH) in Fairbanks, Alaska revealed significant levels of representative components. A fairly constant PAH pattern was observed throughout the winter of 1976-77, and the absolute PAH level correlated with air stagnation. Consideration of relative levels of individual PAH components reveals vehicular emissions as the major source but also provides evidence for contributions from power plant emissions. Fairbanks' PAH levels approach those of major cities in more moderate climates, and this situation emphasizes the importance of air quality problems in development of the Arctic.
Three records of hooded seals, Cystophora cristata Erxleben, from the western Beaufort Sea were obtained between 1970 and 1975. Two of these sightings were verified. The third seal was identified based on descriptions from Eskimo informants. During a period of 106 days in captivity, seal Number 2 increased in weight by 51% at a rate of 0.45 kg per day. Its length increased by 12.3 cm.
Feeding of bearded seals in the Bering and Chukchi Seas and trophic interaction with Pacific walruses
Arctic, v. 33, no. 2, June 1980, p. 330-342, ill., tables
ASTIS record 4528
Current and historical information about food habits of bearded seals, Erignathus barbatus, are presented. Shrimps, crabs, and clams are overall the most important prey. Proportions of different prey in the diet vary with age of seals, location, and time of year. Foods of male and female seals are similar. Young seals eat proportionally more shrimps than do older animals. Recently, clams were important in the diet only in Norton Sound and near Wainwright, and only during late spring and summer. Greatest quantities of food were found in stomachs of seals which had eaten mostly clams. In Bering Strait, seals taken in spring 1958 and 1967 had consumed large quantities of clams, but this item was only a minor fraction of foods in 1975-79. Walruses, Odobenus rosmarus, have increased steadily in numbers since 1960. Whereas Bering Strait was mainly a route through which walruses migrated in spring and autumn, this region is now an area in which large numbers (up to 80,000) spend portions of the summer and autumn. The walruses feed mainly on clams. Increased foraging activity of walruses may have reduced availability of this food item for bearded seals. The walrus population currently appears to be exhibiting indications of stress. These indications may be a reflection of walrus numbers at or in excess of the ability of the clam resource to withstand current predation by walruses. Indices of population condition in bearded seals have remained stable, perhaps due to their more euryphagous habits.
Powdered calcium carbonate (CaCO3) patches averaging 4 cm in thickness were found on icings (aufeis fields) in the Canning and Shaviovik Rivers in northeastern Alaska. The presence of this material on aufeis suggests that much of the water which feeds the aufeis is coming from depth and has flowed through calcareous bedrock. Aufeis forms during the winter at or below the point where groundwater discharges, or when river water is forced upwards through cracks in river ice. Calcium carbonate in solution in the groundwater is excluded as the water freezes during ice growth. The CaCO3 slush then accumulates on top of the ice as the aufeis ablates during the melt season. Four patches of CaCO3, covering approximately 0.1% of the total area of the Canning River aufeis were observed during the July 1978 field study. It is estimated that approximately 540 m³ of CaCO3 precipitate were present in the Canning River aufeis in July of 1978. If similar percentages of CaCO3 precipitate were present on other major aufeis fields on the eastern North Slope, approximately 18000 m³ of CaCO3 may be present during a given year in the major North Slope aufeis fields. Most of this precipitate is deposited into the Arctic Ocean via river flow.
Six periglacial features (sorted polygons, sorted steps, sorted nets, sorted stripes, sorted circles, felsenmeer and a possible altiplanation terrace) are described from a new location in Central British Columbia (locally known as Morfee Mountain, 55 deg. 26 sec. N, 123 deg. 02 sec. W) between 1300-1650 m elevation. These features are local in distribution over an area of several square km. Observations on specific features indicate a continuum of intermediate forms between sorted nets, sorted polygons and sorted stripes. The elevation of these features supports the suggestion of Brown and Pewe (1973) that the lower elevation of permafrost and periglacial features should rise progressively southward along a north-south transect through the Western Cordillera.
Palsas in the Fourth of July Creek valley, B.C., Canada are round- or oval-shaped single hummocks with cores of silty permafrost. Their height ranges from 0.5 to 3 m. The top layer of the studied palsa is only 7 cm peat. In the frozen silt core are found segregated ice lenses up to 15 cm thick. The 0.006-0.02 mm size fraction of the core material of the palsa constitutes 55%. Carbon fourteen datings of the organic material of two different layers in the core of the palsa gave 7470 ± 180 and 7990 ± 180 years B.P. Special attention is given to the unusual sequence of dates obtained and to the pollen stratigraphy. The material is explained by redeposition by flood water into a pond and later uplifting by frost. No evidence of mixing of the original bottom sediments is found.
Analysis of 840 arctic fox (Alopex lagopus) feces (scats) from Prince of Wales Island, indicate that collared lemming (Dicrostonyx groenlandicus) are the most frequent food item. Caribou (Rangifer), arctic hare (Lepus arcticus) and ermine (Mustela erminea) were less important. Bird remains were not prevalent in the arctic fox scats. A marked difference was found between prey items at a den site and those recovered in scats from general searches. Caribou remains were more prevalent in scats from a den site because adult foxes were scavenging nearby wolf kills.
From 19 to 23 July 1979, the authors conducted surveys by foot of the avifauna of Deception Bay, Quebec (62 deg. 07 sec. N, 74 deg. 40 sec. W). ... Sightings and evidence of Tree Sparrows were limited to areas of mixed shrub habitat dominated by Dwarf Birch ... and several species of willow .... Also associated only with this habitat were redpolls ... Savannah Sparrows ... and White-crowned Sparrows .... A sighting warranting further investigation was that of a pair of Hoary Redpolls ....