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Sherwood Park, Canada

Patterson W.F.,Alberta Conservation Association | Sullivan M.G.,Environment Canada
Human Dimensions of Wildlife | Year: 2013

Stocking catchable-size trout to create sport fisheries is based on a simple conceptual model: stocking more fish creates better fisheries that attract more anglers. Organizations typically stock variable densities of fish (i.e., cost) and expect correlated responses in catch rate and angler effort (i.e., benefit). We tested the assumptions inherent in stocked rainbow trout fisheries in Alberta and found no correlation between these costs and benefits of stocking. Rather, stocking low or high densities of trout created low-density stocks that supported low-catch-rate fisheries, but attracted many anglers if catch rates exceeded 0.08 trout/angler-hr and lakes were close to anglers' homes. We propose a fiscally responsible model of stocking (i.e., stock minimum numbers of fish to remain above an optimal catch rate at lakes selected to attract anglers) that allows managers to either increase stocking sites or reduce stocking costs while maintaining angler effort. © 2013 Copyright Taylor and Francis Group, LLC. Source

We tested the general predictions of increased use of nest boxes and positive trends in local populations of Common Goldeneye (Bucephala clangula) and Bufflehead (Bucephala albeola) following the large-scale provision of nest boxes in a study area of central Alberta over a 16-year period. Nest boxes were rapidly occupied, primarily by Common Goldeneye and Bufflehead, but also by European Starling (Sturnus vulgaris). After 5 years of deployment, occupancy of large boxes by Common Goldeneye was 82% to 90% and occupancy of small boxes by Bufflehead was 37% to 58%. Based on a single-stage cluster design, experimental closure of nest boxes resulted in significant reductions in numbers of broods and brood sizes produced by Common Goldeneye and Bufflehead. Occurrence and densities of Common Goldeneye and Bufflehead increased significantly across years following nest box deployment at the local scale, but not at the larger regional scale. Provision of nest boxes may represent a viable strategy for increasing breeding populations of these two waterfowl species on landscapes where large trees and natural cavities are uncommon but wetland density is high. © 2011 by the author(s). Published here under license by the Resilience Alliance. Source

Stevens C.E.,Golder Associates | Counci T.,Alberta Conservation Association | Sullivan M.G.,Alberta Fish and Wildlife
Water Quality Research Journal of Canada | Year: 2010

Economic developments in Alberta have resulted in widespread changes in land use that may deteriorate river conditions for fish. Fish assemblages were characterized with index of biological integrity metrics for the heavily-developed watershed of the Battle River, Alberta. Metric relationships with human stressors were quantified using regression and information theory methods. Although the fauna comprised 14 native species, 50% of the catch was white sucker (Catostomus commersoni Lacepede, 1803). Five statistically unrelated metrics were identified as being responsive to stressors: two trophic guilds, one habitat guild, one reproductive guild, and one measure of community structure. Regression showed that the cumulative effect of human developments, indexed as road density in the basin, was negatively linked to the relative abundance of lithophils and positively linked to the relative abundance of omnivores. Agriculture also threatened the integrity of fish assemblages. Stream sections with higher cattle densities in their basins had fewer lithophils and benthic invertivores; whereas stream sections with higher nutrient concentrations contained fewer species, as well as fewer top carnivores, but more true omnivores. Understanding effects of human footprints that are expanding in western Canada will be critical to the successful management of aquatic resources. © 2010, CAWQ. Source

Warnock W.G.,University of Lethbridge | Blackburn J.K.,Alberta Conservation Association | Rasmussen J.B.,University of Lethbridge
Transactions of the American Fisheries Society | Year: 2011

Genetic assignment methods were used to assign 104 adult migrant bull trout Salvelinus confluentus from five recreational fisheries in theOldmanRiver drainage (Alberta, Canada) to a baseline of three coarse-scale genetic stocks that had been previously identified with a model-based Bayesian clustering method. Based on individual assignment and genetic stock identification,most fisheries were largely dominated by the stock with the most proximate spawning tributaries; however, assignment tests suggested variation among source stocks in the proportions of long-range (>90 river kilometers) migrants relative to short-range migrants (i.e., that used nearby river systems draining spawning streams).Migrants originating from a subset of the drainage were then subjected to a finer-scale mixed-stock analysis in which populations at near-tributary scales were used as the baseline. These stock proportions were compared with estimates from direct observations and were found to yield similar values to stock proportions derived from 2 years of trapping in several spawning streams. These genetic assignment methods may be used to infer contributions of large and fine-scale hierarchical populations to mixed-stock recreational fisheries and are especially applicable for use by inland recreational fisheries managers, which have traditionally not taken advantage of spatial genetic analysis tools to the extent used by coastal commercial fisheries managers. © American Fisheries Society 2011. Source

Braid A.C.R.,University of Alberta | Manzer D.,Alberta Conservation Association | Nielsen S.E.,University of Alberta
Forest Ecology and Management | Year: 2016

Productive grizzly bear foraging habitats are lost as the prevalence of natural forest openings declines. We assessed the effectiveness of using wildlife habitat enhancements to increase food supply for grizzly bears in recent forest harvests by conducting planting trials of containerized shrub seedlings for three important late-season grizzly bear foods (fruiting shrubs): Shepherdia canadensis (Canada buffaloberry), Vaccinium membranaceum (mountain huckleberry), and Amelanchier alnifolia (saskatoon). We monitored seedling survival over two growing seasons and considered the effects of soil nutrient amendments, exclosures, initial seedling condition, and environmental factors (elevation and terrain). A. alnifolia had the highest survival rate, although it may not be as effective in the long term due to being preferred ungulate winter browse. Soil nutrient amendments reduced survival rates of all three species, perhaps due to competition with grasses, whereas exclosures increased survival rates. Survival rates across an elevation gradient for S. canadensis and A. alnifolia were inversely related to local occupancy rates, demonstrating that knowledge of their realized niche space is not consistent with early establishment rates of seedlings. As the amount of natural forest openings declines, wildlife habitat enhancements in disturbed sites with open canopies, including forest harvests, have the potential to locally increase late-season food supply for grizzly bears. © 2016 Elsevier B.V. Source

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