274 research outputs found

    The West Central Alberta Woodland Caribou Landscape Plan: Using a Modeling Approach to Develop Alternative Scenarios

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    Woodland caribou (Rangifer tarandus) are classified as threatened in Alberta. In support of Canada's Species at Risk Act, a Recovery Plan for Woodland Caribou in Alberta was completed in 2004 which required local implementation plans to be completed within 5 areas of the province. The West Central Alberta Caribou Landscape Plan (WCCLP) is the first of these to be initiated and it addresses the recovery strategies for 4 herds. Two aspatial computer models built on the STELLA© modelling platform (ISee Systems, 2007) were used to assist the planning team in evaluating cumulative effects and alternative scenarios for caribou conservation. The ALCES© (Forem Technologies 2008) modelling tool was used to forecast potential changes in the west central Alberta landscape over time. Yearly landscape condition outputs from ALCES© were then exported into a caribou-specific population model, REMUS© (Weclaw, 2004), that was used to project potential population responses by woodland caribou, other primary prey species [moose (Alces alces), elk (Cervus elaphus) and deer (Odocoileus sp.)] and wolves (Canis lupus) (Weclaw & Hudson, 2004). Simulated habitat management strategies that resulted in the highest likelihood of caribou recovery included the maintenance of a high proportion of old forest, the aggregation of industrial footprints and the reclamation of historic seismic lines (although the latter took decades to provide real dividends). Sharing of industrial roads, protection of fragments of old-growth, and expanding an already aggressive fire control strategy in Alberta had little additional effect on caribou recovery. Simulated population management strategies that were successful all involved decades of intensive wolf control, either directly or indirectly through intensive primary prey control (with the exception of woodland caribou) until old-growth forests recovered to densities that provided caribou habitat and decreased alternate prey of wolves. Although this modelling approach makes broad assumptions, it provides simple fundamental relationships that were useful in a multi-stakeholder team setting when evaluating the efficacy of different management strategies for the conservation of woodland caribou

    A Primary Productivity Hypothesis for Disturbance-Mediated Apparent Competition for Boreal Caribou in Canada

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    The most widely reported threat to populations of boreal and mountain woodland caribou (Rangifer tarandus caribou) involves what has come to be known as disturbance-mediated apparent competition (DMAC). Here, anthropogenic and natural disturbances that increase the abundance of deciduous-browsing cervids (e.g., moose [Alces alces] and white-tailed deer [Odocoileus virginianus]) are thought to promote predator (especially wolf [Canis lupus]) numbers, in turn heightening predation risk to caribou. We know most about the hypothesis of DMAC as it relates to caribou where the species is under threat by industry; i.e., from relatively productive southern boreal and mountain systems where landscapes are highly managed and multiple species of predators and ungulate prey interact with caribou. Yet almost 2/3 of extant boreal caribou range occurs in poorly productive, wildfire-dominated areas where caribou compete with only one ungulate species (moose) in the context of DMAC. In Ch. 2, using data specific to the Saskatchewan Boreal Shield, I tested for evidence of DMAC with data specific to an area of previously known low primary productivity. I found that the successional dynamics after fire of the low-productivity boreal shield did not allow for flushes in deciduous browse, meaning moose density could not increase and resulting in no evidence for DMAC in this system. To test predictions consistent with DMAC, in Ch. 3, I examined the relationship between net primary productivity (NPP) with calf recruitment and adult female survival at a national scale. I accounted for variables influencing DMAC, including metrics of large mammal richness, alternative prey biomass, and predator biomass. While geographic site played an important role, NPP was the most important variable in beta regressions, visually influenced PCA dimensionality in the dataset, and was a primary causal factor for reduced caribou survival and recruitment in Structural Equation Models (SEM). The results indicate that NPP and anthropogenic disturbance act as an impetus for DMAC, where the phenomenon is unlikely to occur in low-productivity areas. Overall, I postulate that the DMAC phenomenon is dependent on NPP, or energy in the system, where burned areas of low NPP may not create the conditions necessary for DMAC to occur. Understanding what factors influence where DMAC occurs and at what scale will be critical for determining effective conservation strategies for local caribou range-planning and Canada’s federal Recovery Strategy for boreal caribou

    Winter Habitat Use by Wolves, Canis lupus, in Relation to Forest Harvesting in West-central Alberta

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    Forested landscapes in west-central Alberta are facing increased pressures from forest harvesting and other land-use activities, which may alter the movements and distribution of Wolves and ungulates. Information on habitat use by Wolves in logged forests is scarce, potentially limiting effective land-use planning in the boreal forest. Nine Wolves, from four Wolf packs, were fitted with GPS radiocollars in the Rocky Mountain foothills, near Grande Cache, Alberta (2000-2001). We found Wolves did not use the landscape randomly, but rather exhibited a significant preference for non-forested natural habitats (shrubs, water), relative to their availability. Within forest habitats, Wolves used cutblocks proportionately more than unharvested forest and non-forested anthropogenic habitats (pipelines, clearings); however, selection of forest cutblocks was not statistically significant. We found no evidence that Wolves preferred or avoided forest cutblock edges. Wolf pack territories contained various levels of timber harvesting, but most areas were still in the early stages of harvest. Nevertheless, these areas have been allocated for large-scale harvesting. Understanding the potential responses of Wolves to rapidly changing landscape mosaics poses a significant challenge to researchers and managers, but such information is important to informing future land-management and conservation strategies for boreal forest Wolf-prey systems

    How linear features alter predator movement and the functional\ud response

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    In areas of oil and gas exploration, seismic lines have been reported to alter the movement patterns of wolves (Canis lupus). We developed a mechanistic first passage time model, based on an anisotropic elliptic partial differential equation, and used this to explore how wolf movement responses to seismic lines influence the encounter rate of the wolves with their prey. The model was parametrized using 5 min GPS location data. These data showed that wolves travelled faster on seismic lines and had a higher probability of staying on a seismic line once they were on it. We simulated wolf movement on a range of seismic line densities and drew implications for the rate of predator–prey interactions as described by the functional response. The functional response exhibited a more than linear increase with respect to prey density (type III) as well as interactions with seismic line density. Encounter rates were significantly higher in landscapes with high seismic line density and were most pronounced at low prey densities. This suggests that prey at low population densities are at higher risk in environments with a high seismic line density unless they learn to avoid them

    Land management strategies for the long-term persistence of boreal woodland caribou in central Saskatchewan

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    We investigated landscape changes and their potential effects on woodland caribou-boreal ecotype (Rangifer tarandus caribou) within a portion of the Smoothstone-Wapaweka Woodland Caribou Management Unit (SW-WCMU). The SW-WCMU is one of eight areas delineated by the Province of Saskatchewan for potential recovery planning efforts for boreal caribou, and is one of four management units located on the Boreal Plain Ecozone. The Prince Albert Greater Ecosystem (PAGE) study area was selected within the SW-WCMU for intensive study from 2004 - 2008. Studies focused on quantifying a suite of landscape and population parameters. This paper presents a summary of study results to date and recommends land management strategies intended to contribute to the long-term viability of boreal caribou in the central boreal plain ecoregion of Saskatchewan. The PAGE study area has undergone structural changes from an area that historically presented a lesser amount but well connected mature coniferous forest, to a currently larger amount of mature coniferous stands fragmented by a highly developed network of roads and trails. Movement data pointed to highly clustered use of the landscape by small groups of caribou and smaller home ranges when compared to 15 years ago. Calving sites were located within each individual home range in treed peatland and distant from hardwood/mixedwood forest stands, roads and trails access. Adult annual survival rates were low, averaging 73% over the course of the study. In order to ensure a self-sustaining population level, study results clearly point to the need for landscape restoration to reduce the level of anthropogenic disturbances in some key parts of the study area. Key strategies include retention of mature softwood forest interior proximate to local areas of caribou activity, protection of calving habitat, improving structural connectivity, planning disturbances (forest harvesting, fire salvage, resource exploration, access development) in ways to minimize the anthropogenic footprint, and recovery action planning integrated with other land-use planning initiatives

    Habitat Restoration as a Key Conservation Lever for Woodland Caribou: A review of restoration programs and key learnings from Alberta

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    The Recovery Strategy for the Woodland Caribou (Rangifer tarandus caribou), Boreal Population in Canada (EC, 2012), identifies coordinated actions to reclaim woodland caribou habitat as a key step to meeting current and future caribou population objectives. Actions include restoring industrial landscape features such as roads, seismic lines, pipelines, cut-lines, and cleared areas in an effort to reduce landscape fragmentation and the changes in caribou population dynamics associated with changing predator-prey dynamics in highly fragmented landscapes. Reliance on habitat restoration as a recovery action within the federal recovery strategy is high, considering all Alberta populations have less than 65% undisturbed habitat, which is identified in the recovery strategy as a threshold providing a 60% chance that a local population will be self-sustaining. Alberta’s Provincial Woodland Caribou Policy also identifies habitat restoration as a critical component of long-term caribou habitat management. We review and discuss the history of caribou habitat restoration programs in Alberta and present outcomes and highlights of a caribou habitat restoration workshop attended by over 80 representatives from oil and gas, forestry, provincial and federal regulators, academia and consulting who have worked on restoration programs. Restoration initiatives in Alberta began in 2001 and have generally focused on construction methods, revegetation treatments, access control programs, and limiting plant species favourable to alternate prey. Specific treatments include tree planting initiatives, coarse woody debris management along linear features, and efforts for multi-company and multi-stakeholder coordinated habitat restoration on caribou range. Lessons learned from these programs have been incorporated into large scale habitat restoration projects near Grande Prairie, Cold Lake, and Fort McMurray. A key outcome of our review is the opportunity to provide a unified approach for restoration program planning, best practices, key performance indicators, and monitoring considerations for future programs within Canada

    Climate and management interact to explain the decline of woodland caribou (Rangifer tarandus caribou) in Jasper National Park

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    Woodland caribou in the southern portion of Jasper National Park have declined from an estimated 435 in the mid 1970s to a population estimate of 87 in the fall of 2009. We examined the available historical information to determine why caribou have declined. We compared three main hypotheses for caribou decline in JNP: human disturbance, climate change, and wildlife management. We used historical human use statistics, climate data, and animal abundance information to weigh the evidence for these competing hypotheses over two time scales. Caribou decline could not be attributed to changes in climate over the long-term, or an increase in human use (our proxy for disturbance). Caribou decline was attributed to a combination of climate and wildlife management. Recovery of caribou in Jasper National Park will likely be contingent on managing the interaction between the predator/prey dynamic and climate change

    Impacts of industrial developments on the distribution and movement ecology of wolves (Canis lupus) and woodland caribou (Rangifer tarandus caribou) in the South Peace region of British Columbia.

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    Habitat alterations from anthropogenic disturbances across northeastern British Columbia have resulted in large-scale modifications to predator-prey dynamics. I used GPS collar locations and field data to quantify the responses of wolves (Canis lupus) and woodland caribou (Rangifer tarandus caribou) to the cumulative effects of industrial disturbance. I developed seasonal resource selection functions for caribou and count models of habitat occupancy for wolves. I also related wolf movements to caribou habitat and industrial features. Caribou occupying the boreal forest likely are more at risk from industrial developments. My results suggest that caribou occupying these ecosystems are subject to disturbance by human activity and a greater risk of spatial interactions with wolves. However, these relationships are complicated by the positive and negative responses of wolves to landscape change and the distribution of other prey and predator species. --P. i.The original print copy of this thesis may be available here: http://wizard.unbc.ca/record=b180568

    Putting the environmental impact assessment process into practice for woodland caribou in the Alberta Oil Sands Region

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    Since 1985, woodland caribou (Rangifer tarandus caribou) have been designated as a threatened species in Alberta. Populations studied since the 1970s have been stable or declining, with no population increases documented. Resource expansion into previously undeveloped areas and associated increases in access have been implicated as possible causes for the declines. To facilitate development on caribou ranges, while ensuring the integrity and supply of caribou habitat, standing committees have been formed. The primary role of the committees is to act as advisory bodies to the government and to search for effective and efficient industrial operating guidelines. Recent research has been conducted on the responses of woodland caribou ecotypes to increased human and predator access. Based on this research, operating guidelines have been refined and implemented through Caribou Protection Plans. I discuss how the current operating guidelines are put into practice and linked to the Environmental Assessment process within the Oil Sands Region of Alberta. In particular, I discuss the origination of impact predictions, specific mitigation measures to reduce impacts and monitoring

    Woodland caribou calf recruitment in relation to calving/post-calving landscape composition

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    Since the 1990s, Newfoundland’s woodland caribou (Rangifer tarandus caribou) population has declined by an estimated 66%. Low calf recruitment has been associated to the decline, possibly triggered by increasing calf predation and/or decreasing resources. To investigate the role of landscape composition in this system, we studied the yearly (2005-2008) calving/post-calving range (CPCR) of 104 satellite-collared females belonging to six herds. We mapped nine disturbance factors (e.g. roads, logging, etc), as well as vegetation cover types (e.g. coniferous, deciduous forests, etc), and determined the total area they occupied within CPCRs yearly for each herd. Using an information theoretic approach, we assessed the model that best explained variation in recruitment using these components. Based on corrected Akaike Information Criterion, the model that best explained variation in calf recruitment included total disturbance and deciduous forest area, both showing the expected negative relationship with calf recruitment. Other landscape variables among the models with ΔAICc < 2 were mixed forest, also with a suggested negative relationship, and barrens and wetlands with a significant positive trend. This study highlights the need to minimize total disturbance footprint and account for resulting changes in forest composition within CPCRs during land use planning. Expanding forestry operations and road infrastructure in critical woodland caribou habitat across Canada may additionally contribute to habitat loss via fragmentation. This in turn, may lead to range recession beyond the initial local avoidance footprint. We see the possibility of using calf recruitment models based on landscape parameters, among others, to predict the impact of new industrial developments on calf recruitment
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