Stability and fragility in Arctic ecosystems / Dunbar, M.J.
Arctic, v. 26, no. 3, Sept. 1973, p. 178-185
ASTIS record 10229
The conclusions reached in this paper, concerning the "Fragile Arctic" are the following: 1) Two definitions of ecological stability are in use, and it is essential to keep them separate and explicitly stated. "Type-l stability" is the condition of non-oscillation, or nearly non-oscillation and steady state found in certain tropical situations, the result of continued evolution toward greater economy of energy and involving high information content and low production/biomass ratio. This type of stability is highly vulnerable to serious perturbation, to which it cannot adapt. Such systems may thus be called "fragile" and they are found in the tropics and perhaps in certain parts of high latitude systems, such as lakes, subarctic forests and perhaps the tundra vegetation itself. "Type-2 stability" is the condition of ability to absorb serious perturbation and return to a stable state, usually the status quo ante. This involves system oscillation, smaller information content, higher production/biomass ratios, and lesser economy of energy use. This type is found in mid and high latitudes, in which the physical environment itself oscillates considerably. 2) In tundra environments, extreme ecosystem simplicity in the animal communities leads to extreme oscillation, and it is suggested that such oscillations can be tolerated only if the geographic scale is large, which it is in the Arctic. 3) "Thermokarst", or damage to tundra terrain by damage to, or removal of, the active layer, is a serious hazard which is well understood and can be easily avoided. It is upon this that the "fragile Arctic" reputation is founded. 4) Oil in arctic sea water constitutes a serious hazard, probably more serious than in warmer waters.
Birds of Nuvagapak Point, northeastern Alaska / Andersson, M.
Arctic, v. 26, no. 3, Sept. 1973, p. 186-197, 1 ill., 1 map
ASTIS record 10230
Fifty-two bird species were observed between 12 June and 4 July 1970 in the coastal plain near Nuvagapak Point, northeastern Alaska. Habitat preferences were studied. Nesting was established or seemed probable in 25 species, and a further 5 may have been breeding. Among these were 2 species of Gaviiformes, 7 Anseriformes, 16 Charadriiformes, and 2 Passeriformes. Most birds were associated with some form of surface waters. Among the 8 predators, 6 were largely rodent hunters. Between mid June and early July, these species decreased markedly in abundance together with brown lemmings.
Some observations on witchcraft : the case of the Aivilik Eskimos / Hippler, A.E.
Arctic, v. 26, no. 3, Sept. 1973, p. 198-207
ASTIS record 10231
Cultural and psychological theories of witchcraft are related in order to develop a more comprehensive theory. The proposed integrative schema is applied to witchcraft among the Aivilik Eskimos. Using a theoretical approach, continuities in pre- with post-contact witchcraft are related to Eskimo "cultural personality." Changes are shown to be more illusory than real, and when real, to be related to new social and cultural circumstances in which the continuing personality pattern must operate.
A thermodynamic model of an Arctic lead / Schaus, R.H. Galt, J.A.
Arctic, v. 26, no. 3, Sept. 1973, p. 208-221, ill.
ASTIS record 10232
A time-dependent, two-dimensional thermodynamic model of an open lead in central arctic sea ice is presented. The effects of various advective parameterizations and temperature and salinity profiles on the nature of ice formation are investigated as the lead refreezes. Velocity and stratification under the lead appear to impose secondary but significant constraints on the rate of refreezing. This suggests the existence of regional variations in the heat loss per lead as a function of purely oceanographic factors.
Notes on the oceanography of d'Iberville Fiord / Lake, R.A. Walker, E.R.
Arctic, v. 26, no. 3, Sept. 1973, p. 222-229, ill., 1 map
ASTIS record 10247
The oceanography of a small arctic fiord has been studied over a period of three years. The shallow water structure is determined by convection in the fiord, as is shown by temperature-time series and budget studies. The fiord contains temperature inversions at shallow depths, which have been present in observations over several years. The deeper water structure is determined by the sill across the fiord mouth and similar sills in Nansen Sound that restrict free access at depth of water layers from the Arctic Ocean.
Seasonal climatic fluctuations on Baffin Island during the period of instrumental records / Bradley, R.S.
Arctic, v. 26, no. 3, Sept. 1973, p. 230-243, ill., 1 map
ASTIS record 10233
Temperature and precipitation records for Baffin Island are examined on a seasonal basis for the last 40 to 50 years. Accumulation season temperatures (September to May) during the late 1960s were similar to those that prevailed 30 to 40 years ago. Ablation season temperatures (June, July, August) during the same period were cooler than for at least 30 years. Precipitation variations showed much less spatial coherence, but during the last 10 to 15 years there have been marked increases, mostly during winter months. These increases, accompanied by cooler summers and warmer winters, have led to increased glacierization of the area. The most recent fluctuation of summer temperatures is related to changes in the frequency of synoptic types in the area. Baffin Island is sensitive to small changes in climate that are only revealed by an analysis of temperature and precipitation on a seasonal basis.
Classification and relief characteristics of northern Alaska's coastal zone / Hartwell, A.D.
Arctic, v. 26, no. 3, Sept. 1973, p. 244-252, 1 map
ASTIS record 10234
Four main genetic coastal types are proposed to classify the shoreline of northern Alaska bordering the Chukchi and Beaufort Seas, which extends for more than 2,150 km. from Cape Thompson eastward to the Canadian border: Land erosion - coast marked by subaerial erosion of terrestrially shaped land forms and partly drowned by rise in sea level (8.9 per cent of coastline); River deposition - coast formed by fluvial deposition (19.9 per cent); Wave erosion - coast shaped primarily by marine agencies and expos to the open ocean, being marked by coastal retreat and negligible nearshore deposition (37.5 per cent); Marine deposition - similar to preceding except nearshore sediment deposition is pronounced (33.7 per cent). Four categories of coastal relief or sea cliff height associated with these coastal types are proposed: Low relief - less than about 2 m; Moderate relief - about 2-5 m; High relief - about 5-8 m; Very high relief - greater than about 8 m. About 1590 km or 74% of the coast has relief of 5 m or less whereas mean relief or scarp height for the entire coast is about 4 m. In general, mean scarp heights decrease to the east along the coastal plain.
The local ecological effect of Long-tailed Jaegers nesting in the Subarctic / Price, L.W.
Arctic, v. 26, no. 3, Sept. 1973, p. 253-255, 1 ill., 1 map
ASTIS record 10235
While carrying out geomorphological field work in the Ruby Range, Yukon Territory ... during the summers of 1967 and 1968, an extension of the known breeding grounds of the long tailed jaeger (Stercorarius longicaudus) was observed. A pair of these birds nested on the same southeast-facing slope both years and their presence affected the local ecology in significant ways. For example, they maintained a constant vigil and promptly chased away any predator which came close to the slope. This provided an umbrella for other animals on the slope such as ground squirrels, pika, marmot, and ptarmigan. As a result the population of these animals was higher and their behaviour was more uninhibited than in surrounding areas. This became even more noticeable, by contrast, upon returning to the field in the summer of 1972 and finding the jaegers missing. The feather remains of one adult jaeger were discovered and the atmosphere on the slope was very different. ...Although the Ruby Range is approximately 900 km south of the previously documented nesting area of the long tailed jaeger, several jaegers were sighted here. My research was concerned with solifluction lobe development in the Ruby Range and detailed work was carried out on four adjacent slopes facing southeast, southwest, east, and north. ... The jaegers' nest was located in approximately the same place both years, on a lobe tread in a small basin between two mossy hummocks. ... Occasionally we would hear the jaegers begin their high shrill calls and look in the direction they were flying to see an eagle .... The same treatment was allotted other predators such as wolf, fox, bear, and wolverine. ... The virtual elimination of predators from the slope during the summer was somewhat counterbalanced by the jaegers themselves, however, since they harvested many small rodents on the slope, i.e., shrews, lemmings, voles, and mice of various kinds. But for the larger burrowing mammals, such as ground squirrels, pika, marmot, as well as the ptarmigan, it provided a rather trouble-free existence. On a comparative basis the population of burrowing animals was vastly greater on the southeast-facing slope than the other exposures, and although the major explanation for this may be because of the more favourable environment on the south-east, it is nevertheless felt that the jaegers' presence contributed significantly to the relatively high population. ... there was a clear and observable difference in the ecology of the slope because of the jaegers' presence. Such ecological relationships are replete in nature and we have a great deal to learn about and from them.
An archaeological site on the north coast of Ellesmere Island / Hattersley-Smith, G.
Arctic, v. 26, no. 3, Sept. 1973, p. 255-256
ASTIS record 10236
In July 1965, at the end of a long walk westward from Alert, I marked down an Eskimo site on the south side of the well-developed delta terrace at the mouth of the Wood River, 82°30' N, 63°07' W. In setting and lay-out it resembled sites of the Independence I and II cultures that we found at Tanquary Fiord in 1963 .... It was not until August 1972 that I was able to revisit the delta of the Wood River.... The Eskimo site is 11.5 m above sea level ... and lies 3 m from the edge of the delta terrace and about 60 m from the sea. The level terrace, composed mainly of shingle and gravel with scattered flat rocks and small boulders, ends above the foreshore in a steep bank, the material of which is more or less at angle of rest and lightly vegetated. The distinctive feature of the site is the central hearth, which measures 260 cm in length by 69 cm in breadth. It is oriented at right angles to the shore so that the entrance of the tent ring faces the sea, and it is formed in the usual way of flat slabs (in this case 3 in number) of fissile rock set on edge in the ground. Outside the central hearth only 4 rocks define the tent ring .... About 6 m to the north of this main structure there is a rough circle (1.5 m in diameter) of small boulders, and a similar feature 35 m to the south; the latter comprises 6 boulders with maximum dimensions of 35 cm set on the arc of a rough circle about 2 m in diameter. The site is protected to the south by a cliff in bedrock to a height of about 100 m. In the middle of the central hearth, with minimum disturbance of the floor, we made a small collection of charcoal and charred bones for radiocarbon dating. Radiocarbon analysis of the charcoal ... has yielded an age of 1070 ±270 yr BP .... The discovery of the Wood River site raises the question of how many others remain to be discovered on the north coast of Ellesmere Island. Very little is to be seen at the surface, and it is likely that similar sites in the Alert area to the east have escaped notice, although by now they may have been destroyed by the passage of vehicles. On the long coast of northern Ellesmere Island no other archaeological sites have been found but then few people have had the interest and opportunity at the right time of year to look for them. ... Two further comments are offered with diffidence, since I am not an archaeologist. First, the radiocarbon age of the charcoal, if it can be accepted as a maximum age for occupation of the site, belies what appeared to be a distinctive feature of the Independence culture, namely the central hearth. Can it be that this was a feature that persisted to the end of the Dorset period in certain areas? Secondly, on the question of the movement north of these Eskimos, they may all have crossed the plateau southwest of the Grant Ice Cap from the Lake Hazen area and then followed the valley of the Wood River to its mouth, thus by-passing the Robeson Channel coast. From excavations in 1958, Dr. M. S. Maxwell concluded that hunters from the south visited the Lake Hazen area during the period from about A.D. 1000 to 1450. However, sites of both Independence and Thule cultures have since been found at the head of Tanquary Fiord .... Thus, although Maxwell found no evidence that Eskimos had made the passage from Tanquary Fiord to Lake Hazen, it now seems certain that immigration came from that direction at some time, thus completely by-passing the Smith Sound route.
Pollutant and shell thickness determinations of peregrine eggs from West Greenland / Walker, W. Mattox, W.G. Risebrough, R.W.
Arctic, v. 26, no. 3, Sept. 1973, p. 256-258
ASTIS record 10237
A preliminary survey of breeding peregrine falcons (Falco peregrinus) in West Greenland in 1972 indicated both a high nesting density (one pair per 100 square miles) and a high production rate (2.25 young per pair or 2.57 per pair with young). ... Peregrines in the eastern United States and southern Canada experienced an increasing incidence of reproductive failures throughout the 1950s and early 1960s, culminating in the disappearance of the breeding populations by 1964. Studies were therefore carried out in the Northwest Territories and Alaska in 1966 to determine the status of the northern birds. No apparent abnormalities were found, and the reproduction was considered to be normal. ... Thin eggshells have been a characteristic of all the declining populations. The degree of thinning is closely associated with levels of the DDT compound p,p'-DDE in the eggs .... We have therefore examined the eggshells and shell fragments obtained in Greenland in 1972 for evidence of shell thinning and have measured the chlorinated hydrocarbons in two unhatched eggs. During the 1972 Greenland peregrine survey, 1 unhatched egg was collected from each of 2 eyries. In addition, shell fragments of 7 hatched eggs from 4 different females were collected. The mean thickness of these 9 eggs from 6 females was 0.298 mm ±0.018 (95 per cent C.L.: range 0.26-0.33), 14 per cent lower than the mean thickness of 42 peregrine eggs from Greenland that were collected before 1940 (thickness = 0.347 mm ±0.018 ...). Shell thinning of unhatched and broken eggs obtained from Ungava in 1967 and 1970 was somewhat more severe; the mean thickness was 21 per cent less than that of 59 peregrine egg-shells collected in the eastern Arctic between 1900 and 1940. ... DDE concentrations, expressed on either a wet weight or a lipid weight basis are within the range of those measured in peregrine eggs from Alaska and northern Canada. Polychlorinated biphenyls (PCB) have not previously been determined in peregrine eggs from the Arctic. Levels in the Greenland eggs were comparable to those of DDE .... The composition of the PCB mixture was similar to that of commercial mixtures containing 60 per cent chlorine by weight, Profiles of PCB residues in these eggs are strikingly like those of fat biopsies from peregrines in Chile, a further example of the global nature of the contamination to which this species is exposed. Body burdens of organochlorine compounds in the West Greenland peregrines are not therefore sufficiently high to affect reproductive success; the pollution ecology of this population might be considered comparable to that of other arctic-breeding peregrines in the mid-sixties. These also had comparatively high organochlorine levels with no apparent effect on reproduction, but many eggs approached a critical level of shell thinning. Because of the close relationships found in other populations between DDE concentrations and the degree of shell thinning and associated reproductive failures, we conclude that a comparatively small increase in the DDE levels to which these birds are exposed would endanger the population.
The Icefield Ranges Research Project, 1972 / Ragle, R.H.
Arctic, v. 26, no. 3, Sept. 1973, p. 258-263
ASTIS record 10238
The Icefield Ranges Research Project (IRRP) base camp (61° N, 138°30' W) opened its doors on 3 June. ... Four programs, supported in whole or in part by the project, were in the field before the official opening of Kluane base camp, and two research teams remained in the field through early September. From 3 June until 29 August base camp was in full operation. A total of 86 persons representing 23 colleges, universities, and institutions (12 Canadian; 11 U.S.) made use of IRRP facilities during that time. One student from the United States and 6 Canadian students were involved in field work leading to postgraduate degrees: 4 toward an M.Sc. and 3 toward a Ph.D. Peak occupancy was in the last two weeks of July and the first week of August when over 50 people were at Kluane and the 15 long- and short-term field camps. The February 1972 announcement of a Kluane National Park has generated interest in a number of multi-year programs concerned with resource inventory and planning processes. ... Under the auspices of the Arctic Institute's Visiting Scientists program two professors from the Departments of Geography at the University of Glasgow, Scotland, and Western Michigan University, Kalamazoo, took part in IRRP during the last week in July and first week in August. ... Air support for IRRP, including support for the television team and climbing expeditions, was provided by the Arctic Institute's supercharged, ski-wheel-equipped Helio Courier; by a Canadian Forces DeHavilland Buffalo; and by a chartered Bell Ranger helicopter. A total of approximately 215 hours were flown in support of all programs in 1972. The twenty-foot long, wide-beam life boat was in greater demand this past summer than in any summer since 1968. ... [Research updates were provided for: 1) Glacier studies (Geophysical measurements - Tapridge and Rusty glaciers, Thermal drilling - Steele Glacier, Tapridge Glacier - survey, Glacier inventory, Kaskawulsh Glacier); 2) Glacial geology, geomorphologyand hydrology (Donjek Glacier - ice cored moraines, Donjek and Kaskawulsh glacier termini - load distribution variation and source, Slims River valley - loess transport, Donjek valley - Spring Creek alluvial fan, Ruby Range - mass wasting program), 3) Kluane Lake studies (Raised beaches - drowned forest, Drainage of glacial Lake Kloo - a reconnaissance, Zooplankton studies), 4) Biology and environmental studies (Studies of Boschniakia rossica, Plant succession on three Kaskawulsh Glacier terminal moraines, Canid predator-prey relationships in Kluane National Park, Ecological studies - Kluane National Park), 5) Archaeology (Ethnohistoric archaeology - Tatshenshini River basin, Kluane Lake - Long Point site); 6) High altitude physiology studies, 7) Mountaineering equipment evaluation program, 8) Meteorology.]
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