The effects of human land use on the winter habitat of the recovering Carcross woodland caribou herd in suburban Yukon Territory, Canada

Carcross woodland caribou (Rangifer tarandus caribou) numbers are increasing as a result of an intensive management and recovery program initiated in 1993. In the last 13 years, three overlapping First Nation land claim agreements were settled resulting in a complicated array of private and public land management authorities on this winter range, situated in the Whitehorse periphery. Twelve years of VHF radio-collar data (1994-2005) and 5 years of GPS radio-collar data (2000-2005) for female caribou were assessed to determine winter concentration areas and important winter habitats. We contrasted locations from 11 GPS radio-collared caribou with land cover classes, derived from classified Landsat 7 imagery, to evaluate the distribution and abundance of preferred habitats within this winter range. We found significant use of Open Needle Leaf lichen vegetation classes and avoidance of the relatively more abundant Closed Needle Leaf class. Our resource selection function model validated the preference for Open Needle Leaf Lichen and determined that caribou were spaced significantly further from an estimate of the human Zone of Influence (ZOI) than was expected from random locations. While our assessment determined that 64% of the winter range was located outside of either private lands or land influenced by human activity, key winter vegetation classes were under-represented within this area. If caribou are to successfully recover on this landscape and persist through time it is essential to manage, through meaningful participation among land management authorities, the remaining caribou habitat for environmental rather than human consumptive values

Evaluating the ecological consequences of human land-use on grizzly bears in southwest Yukon, Canada

Bibliography: p. 209-254Some pages are in colour.This study investigated the effects of human land-use on grizzly bear (Ursus arctos L.) habitat and populations in the Kluane region of southwest Yukon, Canada. Previous studies in the region identify grizzlies as the species most at risk from cumulative impacts of human activity . The goals of this project were to: 1) identify the effects of cumulative human activities on grizzly habitat and populations; and 2) provide recommendations on human-use management with respect to the conservation of grizzlies and their habitat. Thus , I investigated three aspects of bear ecology and synthesized them to examine the influence of human-activities on bears. First, I examined the appropriateness of using Tasselled Cap Transformation variables for representing the distribution of bear forage. Tasselled Cap layers correlated with aggregate measures of forage abundance, provided continuous variables for linear occupancy estimation models, and were more cost-effective to produce than land cover classifications . I then tested the influence of conspecific distribution on habitat selection by grizzly bear sex/age cohorts . Family groups segregated from other cohorts, in part, to avoid intra-specific aggression and to protect cubs. Segregation also occurred because of differential response by each cohort to the distribution of human activity, and the distribution of forage. I next examined the temporal trends and spatial characteristics of grizzly bear mortality in Kluane. While efforts reduced the frequency of occurrences and management-related mortalities, there was a substantial lag between the management efforts and the decline of human bear interactions and human-caused bear mortalities. Increased human activity in the region may have negated the positive effects of landfill closures. Finally , to examine the influence habitat and mortality models had on grizzly bear productivity and survival, I compared the explanatory power of empirical habitat models based on grizzly bear telemetry relocations or forage availability against expert-opinion models. I used the best model, established by model selection criteria, for explaining reproductive and survival rates to predict population status for grizzly bears in Kluane . Survival and productivity of grizzly bears decreased on the periphery of the protected area adjacent to the highways. While productivity in the areas adjacent to the highways was relatively high, mortality was also high . These areas, therefore, were acting like attractive sinks. Reducing human-caused mortality on the Park periphery and developing a transboundary management strategy will be necessary to conserve grizzly bears in Kluane

Gps performance in yukon's arctic coast

<p>This study analyses GPS performance in Yukon's Arctic coast to inform future research that uses this technology in the region. To test this, Telonics GPS collars were placed on stakes during the summers of 2009 and 2010 throughout the region for varying lengths of time. The fix records produced by these collars were then collected and cleaned, leaving 30 samples. Using these records combined with a digital elevation model, eight variables were extracted and analysed in an attempt to find relationships, such that a fix rate could be predicted throughout the landscape. The results indicated that very few strong relationships existed. Densiometer values proved to be the only relationship between an environmental variable and fix rate. Available sky and aspect data produced results that were contrary to those expected. Overall, Telonics Generation 3 collars had extremely high fix rates, high accuracy, and low positional dilution of precision. Moreover, there was little variation in these results. This means that future GPS studies in the region would likely require minimal correction for fix rate bias. However, if corrections were to be made, more data would have to be gathered to ensure the results were statistically sound. The analysis suffered from the limitations of small sample size and low sample variance, among several others. Therefore, future studies should increase the number and diversity of sites tested.</p