The type section of the Vikinghôgda Formation: a new Lower Triassic unit in central and eastern Svalbard

The Vikinghøgda Formation (250 m) is defined with a stratotype in Deltadalen-Vikinghøgda in central Spitsbergen. The Vikinghøgda Formation replaces the Vardebukta and Sticky Keep Formations of Buchan et al. (1965) and the lower part of the Barentsøya Formation of Lock et al. (1978) as extended geographically by Mørk, Knarud et al. (1982) in central Spitsbergen, Barentsøya and Edgeøya. The formation consists of three member: the Deltadalen Member (composed of mudstones with sandstones and siltstones), the Lusitaniadalen Member (dominated by mudstones with thin siltstone beds and some limestone concretions) and the Vendomdalen Member (composed of dark shales with dolomite interbeds and nodules). The Lusitaniadalen and Vendomdalen members replace the former Sticky Keep Formation/ Member in the siirne areu. The Vikinghøda Formation can be followed through central and eastern Spitsbergen to Barentøya and Edgeøya and includes all sediments between the chert-rich Kapp Starostin Formation (Permian) and the organic-rich shales of the Botneheia Formation (Middle Triassic). The subdivision into three members is also reflected in the organic carbon content and palynofacies. Upwards. each succeeding member becomes more distal, organic-rich and oil-prone than the one below.
The Vikinghøda Formation is well-dated by six ammonoid zones. although the transitional beds between the Deltadalen and Lusitaniadalen members lack age diagnostic macrofossils. Corresponding palynozonation and magnetustratigraphy have also been determined. The overall stratigraphical development correlates well with other key Triassic areas in the Arctic, although intervals in the late Dienerian and early Smithian may be condensed or missing.     

Vegetation exploitation by barnacle geese Branta leucopsis during incubation on Svalbard

The paper is a study of vegetation exploitation and the effect of food availability on the diet and behaviour in barnacle geese breeding at Storholmen, Svalbard. Detailed vegetation mapping was used to estimate the availability of food to individual pairs of geese. Diet composition was assessed through analysis of plant fragments in droppings. The behaviour of geese in relation to snowmelt patterns was recorded. Most vegetation types were exploited by the geese either for feeding or as nest substrate. Nest density was highest and territories were smallest on early, snow-free ridges, although late breeding individuals also nested in moss tundra vegetation. Most geese pairs exploited a mosaic of vegetation types in their territories, which extended the feeding period when plants were nutritionally most profitable to the geese. Territory size increased with decreasing density of the highest preferred food plants. Female geese preferred plants with high nutrient quality, and the diet during incubation consisted of 41% flowers of forbs, 19% grasses, 6% leaves and buds of forbs, and 34% mosses. When the availability of grasses was <5%, geese switched to a diet dominated by the abundant, but nutrient-poor, mosses. The nutrient-poor diet resulted in more time off the nest and less time being alert or searching for food during feeding bouts. Because nests are exposed to predators when females feed or search for food, a low availability of nutrient-rich food within the territory can affect hatching success.     

Seasonal changes in crop content of the Svalbard Ptarmigan Lagopus mutus hyperboreus

Crop contents of Svalbard Ptarmigan have been examined. For chicks younger than 25 days the crops contained almost exclusively bulbils of Polygonum viviparum . High incidence of this food item was also found in crops from adult birds during late summer and autumn (July-October). Midwinter (November-February) crops contained a mixture of plant species dominated by herbs like Saxifraga oppositifolia and S. cespitosa , but with a significant contribution from Salix polaris . The proportion of 5. polaris increased throughout the winter and became highly dominant in spring (May-June). During all seasons the birds ingested plant parts of high nutritional value. The change in crop content from P. viviparum to 5. polaris via different herbs was associated with a decrease in the content of crude protein from 20–25% in July-August to about 16% in March-April, and a corresponding increase in crude fibre from about 10% to about 15%. The content of inorganic constituents (P, Mg, Ca, K, Na) varied insignificantly with season and was fairly high.     

Lithological description of subcropping Lower and Middle Triasic rocks from the Svalis Dome, Barents Sea

Eleven shallow cores display 315 m of the >700 m thick Lower and Middle Triasic successional of the Svalis Dome, a Salt diapir in the central south-western Barents Sea. The Svalis Dome was uplifted in the late Mesozoic. and Trisassic rocks suherop below Quaternary till around the Upper Palaeozoic core of the dome. Deposition of the Triassic succession took place in deep shelf to basinal environments below storm wave base. The succession is dated by macrofossils and palynomorphs and can be assigned to four formations. The basal beds of the shaly greenish grey Havert Formation (Griesbachian) occur above Permian bioclastic carbonate. The Klappmyss Formation (Smithian) in the lower part contains gravity flow sands deposited as submarine fans pussible triggered by tectonic movements along the adjacent ault zones overlian by silty claystones. An organic-rich dark shale unit is here formally defined as the Steinkobbe overlain by silty claystones. An organic-rich dark shale unit is here formally defined as the Steinkobbe Formation, and was deposited in a large bight by restricted water circulation. The Snadd Formation. on top, representes a marine shelf unit deposited in front of an emerging land area in the north-east. A minimum of six higher order transgressive-regressive sequences are recognized at the Svalis Dome and these are correlated with other Arctic areas.