Geographical and Ecological Relationships of the Arctic-Alpine Vascular Flora and Vegetation, Arrigetch Peaks Region, Central Brooks Range, Alaska

1989 ◽  
Vol 16 (3) ◽  
pp. 279 ◽  
Author(s):  
David J. Cooper
2019 ◽  
Vol 133 (2) ◽  
pp. 151 ◽  
Author(s):  
Mathew S. Sorum ◽  
Kyle Joly ◽  
Matthew D. Cameron

Salmon (Oncorhynchus spp.) is a key dietary item for temperate coastal Brown Bears (Ursus arctos) across much of their circumpolar range. Brown Bears living in Arctic, interior, and montane environments without large annual runs of salmon tend to be smaller bodied and occur at much lower densities than coastal populations. We conducted ground and aerial surveys to assess whether Brown Bears fished for salmon above the Arctic Circle, in and around Gates of the Arctic National Park and Preserve. Here, we document the use of salmon by interior Brown Bears in the Arctic mountains of the central Brooks Range of Alaska. We believe our findings could be important for understanding the breadth of the species’ diet across major biomes, as well as visitor safety in the park and Brown Bear conservation in the region.


2015 ◽  
Vol 72 (9) ◽  
pp. 2532-2538 ◽  
Author(s):  
Øystein Varpe ◽  
Malin Daase ◽  
Trond Kristiansen

Abstract A gigantic light experiment is taking place in the Arctic. Climate change has led to substantial reductions in sea ice extent and thickness in the Arctic Ocean. Sea ice, particularly when snow covered, acts as a lid hindering light to reach the waters underneath. Less ice will therefore mean more light entering the water column, with profound effects on pelagic and benthic ecosystems. Responses through primary production are so far well acknowledged. Here we argue that there is a need to broaden the view to include light-driven effects on fish, as they depend on light to locate prey. We used the Norwegian Earth System Model estimates of past and future sea ice area and thickness in the Arctic and applied attenuation coefficients for ice and snow to estimate light intensity. The results show a dramatic increase in the amount of light predicted to reach the future Arctic Ocean. We combined this insight with mechanistic understanding of how light modulates visual prey-detection and predict that fish will forage more efficiently as sea ice diminishes and that their populations will expand to higher latitudes, at least seasonally. Poleward shifts of boreal fish species have been predicted by many and to some extent observed, but a changing light environment has so far not been considered a driver. Expanding distributions and greater visual predation may restructure ecological relationships throughout the Arctic foodweb and lead to regime shifts. Research efforts should focus on the dynamics of how less sea ice will affect the feeding ecology and habitat usage of fish, particularly the northern limits of distributions. Mechanistic approaches to these topics offer insights beyond statistical correlations and extrapolations, and will help us understand how changing biophysical dynamics in the Arctic influence complex processes including production, predator–prey interactions, trait-evolution, and fisheries.


1994 ◽  
Vol 68 (6) ◽  
pp. 1235-1240 ◽  
Author(s):  
Mary E. Baxter ◽  
Robert B. Blodgett

A new species of the genus Droharhynchia Sartenaer is established from lower Eifelian strata of west-central Alaska and the northwestern Brooks Range of Alaska. Droharhynchia rzhonsnitskayae n. sp. occurs in the Cheeneetnuk Limestone of the McGrath A-5 quadrangle, west-central Alaska, and the Baird Group of the Howard Pass B-5 quadrangle, northwestern Alaska. These occurrences extend the lower biostratigraphic range of both the genus and the subfamily Hadrorhynchiinae into the Eifelian. They also suggest close geographic proximity of the Farewell terrane of southwestern and west-central Alaska and the Arctic Alaska superterrane of northern Alaska during Devonian time.


ARCTIC ◽  
1958 ◽  
Vol 11 (2) ◽  
pp. 70 ◽  
Author(s):  
Gerald R. McCarthy

Reports incidental observations made in the Barrow-Cape Simpson area 1949-50. Pleistocene glaciers of Alaska did not extend north beyond the northern foothills of the Brooks Range, yet glacial boulders have been reported near and along the coast. Altogether 56 such erratic boulders from sheltered spots on the shore, as far as 8-9 mi inland on the tundra and a few from the present sea floor were examined. Their location and size, rock type with field description and petrographic analysis are tabulated. Of granite (16), diabase (17), quartzite (10), etc., they range in weight from 2-3 lbs. to 4-5 tons. They are thought to represent morainic material left by melting icebergs, and the bergs to have been produced from glaciers in widely separated areas.


2016 ◽  
Author(s):  
Andrew W. Balser ◽  
Jeremy B. Jones ◽  
M. Torre Jorgenson

Abstract. Permafrost landscape responses to climate change and disturbance impact local ecology and global greenhouse gas concentrations, but the nature and magnitude of response is linked with vegetation, terrain and permafrost properties that vary markedly across landscapes. As a subsurface property, permafrost conditions are difficult to characterize across landscapes, and modeled estimates rely upon relationships among permafrost characteristics and surface properties. While a general relationship among landscape and permafrost properties has been recognized throughout the Arctic, the nature of these relationships is poorly documented in many regions, limiting modeling capability. We examined relationships among terrain, vegetation and permafrost within the Brooks Range and foothills of northern Alaska using field data from diverse sites and multiple factor analysis ordination. Terrain, vegetation and permafrost conditions were correlated throughout the region, with field sites falling into four statistically-separable groups based on ordination results. Our results identify index variables for honing field sampling and statistical analysis, illustrate the nature of relationships in the region, support future modeling of permafrost properties, and suggest a state factor approach for organizing data and ideas relevant for modeling of permafrost properties at a regional scale.


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