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Grizzly bears inhabit wilderness areas in the northwestern region of the lower forty-eight states, western Canada, and areas of Alaska. Because of the settlement of the west and loss of prime habitat, populations declined rapidly in the nineteenth century, and in 1975 federal action was taken to protect grizzlies under the Endangered Species Act. Since 1950 about 722 technical papers have been written on the grizzly bear. Major research has focused on ecology, conservation, reproductive biology, behavior, dietetics, anatomy, and physiology, among other topics. Due to geographic distribution of the species, much of the research has been carried out by authors and organizations in western regions of the United States and Canada where major grizzly populations exist. A significant number of technical papers appear in three key journals: Ursus, the Journal of Wildlife Management, and the Canadian Journal of Zoology. According to data in WorldCat, about 1,167 records, covering monographs and technical reports, contain information on grizzlies and present research findings. The bulk of monographs appeal mainly to a general audience. However, citation analysis reveals a core of highly cited technical papers, many written with an emphasis on special themes or topics, whereas others focus on the grizzly itself, all together advancing the science on this species. [ABSTRACT FROM PUBLISHER]

This paper presents a sampling design for monitoring spatial and temporal changes in forest health in the Upper Elbow River Basin, in Alberta, Canada. The procedure involved a combination of cumulative effects assessment and remote sensing techniques for selecting sampling sites based on physical and anthropogenic features. Normalized difference vegetation index (NDVI) was the indicator of forest health. Unique combinations of slope, aspect, soil moisture, NDVI, vegetation type, and the zone of influence of human activities were used to select pairs of sampling sites. Each pair consisted of a site within the zone of influence and one outside the zone. Spatial discrimination analysis was the method used for reclassification. The analysis suggested that 58 pairs would be appropriate for monitoring. NVDI was negatively correlated with dry soils and increased with the slope. To various extents, most of the species displayed NDVI values between 0.20 and 0.59. The density of linear disturbances (km/km2) was estimated and it showed that one of the three sub-catchments, the Bragg Creek, has levels of human disturbance above the value considered optimal for wildlife habitat suitability. [ABSTRACT FROM AUTHOR]

Many factors influence the abundance of migratory tundra caribou (Rangifer tarandus). To understand their interactions with caribou abundance, we need to quantify these factors. In this study, we documented the changes in habitat conditions during winter and pre-calving migration for the Bathurst Caribou herd, using remote sensing data and ground measurements. We found there was a significant decrease in forest area which has abundant lichen, the main caribou winter diet, during recent decades due to increase in burned area, which in turn was positively correlated with summer temperature. For winter forage accessibility, we examined the annual maximum snow depth and mean ice content in snow (ICIS). There was a significant increase in ICIS during 1963–2006, but no trend in the maximum snow depth. During the pre-calving migration, the percent snow cover showed large inter-annual variations but no significant trend. [ABSTRACT FROM AUTHOR]

The combined effects of multiple ecological stressors determine the net impact of global change on environmentally sensitive alpine and polar environments. For example, climate warming and nitrogen deposition both increasingly affect ecosystems at high elevations. We hypothesized that the net impact of warming and nitrogen on alpine plankton differs between consumers and producers because of the greater environmental sensitivity of higher trophic levels. Also, we expected that habitat conditions would mediate the responses of plankton to these two stressors as sediments function as ecological buffers against environmental change. These hypotheses were tested in a growth chamber by applying temperature (8 vs. 15°C) and nitrogen (200 vs. 1000 μg N L-1) treatments to a planktonic alpine community in the presence and absence of sediments obtained from Pipit Lake, Banff National Park, Alberta. A significant nitrogen-temperature interaction affected phytoplankton abundance because the positive effect of fertilization depended on warming. Warming also amplified the effect of nitrogen on herbivores while suppressing the fecundity of omnivores. The presence of sediments suppressed the positive effect of warming on herbivores, but stimulated omnivores. The observed prevalence of non-additive effects highlights the strong potential for global change causing future ecological surprises in alpine environments. [ABSTRACT FROM AUTHOR]

Reports on a study by Peter Blancher regarding the importance of Canada's boreal forest as a breeding ground for songbirds. Bird species that thrive in the forest; Background information on the boreal forest in Canada; Usefulness of boreal trees to newsprinting.

Over the course of the last century, the 9000-km² "Ellesmere Ice Shelf" (82-83°N, 64-90°W) fragmented into six main ice shelves now totaling 1043 km². This ensemble of thick ice environments lies along the northern coast of Ellesmere Island in the Canadian High Arctic and provides a cryohabitat for microbial communities that occur in association with eolian and glacially entrained sediments on the ice surface. We undertook a comparative analysis of physical, chemical, and biological characteristics of five of the remnant ice shelves including geographic information system (GIS) mapping of ice types. Each of these remnants is a thick (<20 m) mass of ice with substantial sediment overburden that promotes the formation of oligotrophic meltwaters in the summer. Microbiota occurred in all sampled sediment, forming a continuum of abundance from sparse to loosely cohesive and pigmented microbial mats. Using digital images from over-flight transects we determined that 8% of the combined ice-shelf area was suitable microbial mat habitat, and contained an estimated 34 Gg of organic matter stocks for the entire system. A gradient of increasing chlorophyll a, organic content, and conductivity was found from west to east. This is likely related to the surface ice type (meteoric versus marine) and to the relative availability of sediment. Our results indicate that differences in phototrophic community structure (microalgae and cyanobacterial morphotypes) were associated with different ice and microbial mat types. In addition, the relative abundance of dominant taxa was significantly associated with environmental gradients of conductivity, soluble reactive phosphorus, and nitrate and ammonium concentrations. There were distinct differences between each ice shelf with regards to ice type and sediment availability but no differences in taxonomic richness or diversity, indicating little effect of habitat fragmentation on these community attributes. However, the ensemble of ice shelves that compose this unique cryoecosystem remains vulnerable to habitat attrition and complete loss with ongoing climate warming. [ABSTRACT FROM AUTHOR]