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Synopsis: The short-horned lizard is Alberta's only lizard. It is indigenous to semi-arid, short grass portions of the northern Great Plains and usually found in rather rough terrain. This report evaluated habitat suitability requirements for the short-horned lizard according to the following parameters: Topographical Features: Most of the daily movement patterns during the summer rarely exceeded 30m, and generally occurred along the slopes of the valleys or valley bottoms. Consequently, all valleys and all prairie habitat within 100m of valleys are considered the best potential habitat. Native Prairie Class: Native Prairie Class (NPC) is derived from the Native Prairie Vegetation Baseline Inventory developed...
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Synopsis: The objective of this study was to examine initial effects of the 2003 Lost Creek wildfire (southwestern Rocky Mountains of Alberta) on concentrations and production (yield and total export) of several nitrogen (N) forms, and to explore initial recovery of these effects within the first 3 years after the fire. During the first postfire year, nitrate (NO3–), dissolved organic nitrogen (DON), and total nitrogen (TN) concentrations in severely burned watershed streams were 6.5, 4.1, and 5.3 times greater, respectively, than those in reference streams. Weaker effects were evident for concentrations of ammonium (NH4+; 1.5 times) and total particulate nitrogen (TPN; 3.0 times). A rapid decline in mean watershed...
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Conclusions: When isolated, larger patch size correlates with higher species density and occurence in area-sensitive grassland birds Thresholds/Learnings: Synopsis: This paper examines the influence of landscape fragmentation and isolation of Conservation Reserve Program (CRP) grasslands on grassland breeding bird populations in the northern Great Plains states. The study explores the relationship between species occurrence and density, and patch size by tracking 15 bird species on 303 restored grassland areas. Locating CRP grassland fields near existing grasslands, or establishing one large CRP field rather than several small fields, benefits area-sensitive grassland bird species. Caveats: Inconsistent findings...
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Conclusions: Valleys are the only areas capable of sustaining sufficient habitat for the butterfly species, Weidemeyer's Admiral. Consequently, all other areas (i.e. plains, uplands, benches, escarpments, plateaus) were deemed unsuitable. Additionally, areas devoid of shrub cover did not meet the habitat requirements of this specialized species. Thresholds/Learnings: Synopsis: Two variables were selected to model potential habitat for the butterfly species, Weidemeyer's Admiral. Topographical features derived from the Agricultural Region of Alberta Soils Inventory Database (AGRASID) and percent shrub cover derived from the Native Prairie Vegetation Baseline Inventory developed by Alberta Environment were used to...
Synopsis: This book provides important foundational concepts in landscape ecology, with a particular focus on the effects of land use and landscape fragmentation. Building on Forman’s patterns of landscape change, the book cites the McIntyre and Hobbs model of landscape change, which suggests that landscape modification often increases through time. Four broad classes of landscape condition can therefore be identified along a continuum of increasing human landscape modification: intact, variegated, fragmented, and relictual (figure 3). Similarly to Forman’s model, these classes represented correspond to different spatial patterns in the landscape. Therefore, as the extent of human land use increases, the amount...
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Synopsis: Natural habitats are considered inherently indispensable to the global economy by conservationists, but few natural ecosystems afford direct and quantifiable economic benefits. Quantification of natural land value can provide compelling evidence favoring preservation over development. Wild bees are important pollinators of many crop plants, and natural patches in agroecosystems enhance pollinator services and crop yield. Bee abundance was greatest in canola fields that had more uncultivated land within 750 m of field edges and seed set was greater in fields with higher bee abundance. A cost–benefit model that estimates profit in canola agroecosystems with different proportions of uncultivated land is presented....
Synopsis: This study aimed to independently examine the effects of varying amounts and configurations of habitat at a landscape scale, with particular attention to critical persistence thresholds. A discrete reaction-diffusion model was used to estimate long-term equilibrium population persistence of a hypothetical species in a patchy landscape. When examined over a broad range of habitat amount and arrangements, population size was largely determined by the proportion of habitat (amount) in a landscape. However, when habitat coverage dropped below 30-50%, population response deviated, coinciding with a persistence threshold. Species persistence declined rapidly at this threshold range (50% for low degrees of aggregation,...
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Conclusions: The amount of upstream impervious area affects downstream fish habitat quality, channel stability, and water quality. The use of riparian buffers can reduce the magnitude of urban impacts, however, they cannot fully mitigate the impacts of upstream development in the watershed. Threshold percentages of impervious areas , as well as the percentage of forest cover in a watershed appear to be the most effective indicators of watershed health. Thresholds/Learnings: Impervious areas should be kept at or below 10% of a watershed, and forest cover should be maintained at a minimum of 65% in order to effectively mitigate the impacts of urbanization and development on watersheds. Synopsis: This paper articulates...
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Conclusions: The goal of the report is to set forth guidelines for increasing greater sage-grouse abundance by at least 33% by 2015, and overall distribution of greater sage-grouse by at least 20% by 2030. In summary, the guidelines presented include steps for improving vegetation management to 1) restore degraded habitat, followed by 2) steps to reduce habitat fragmentation. Thresholds/Learnings: Sage-grouse numbers on leks within 1600m of coal bed methane (CBM) compressor stations were lower than on leks unaffected b this disturbance. All drilling activities for gas and oil development should be prohibited within 5500m of active leks and their associated nesting areas. Leks are frequently abandoned once road use...
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Synopsis: This study monitored the response of a species of pine bark beetle, Trypodendron lineatum, to direct and indirect measures of habitat availability in a forest subjected to various levels of harvest intensities. Four stand types (conifer dominated, mixed, deciduous dominated, and deciduous dominated with conifer understory) were treated with four levels of harvest intensity (unharvested, 50%, 80%, and 90% harvested). Prior to harvest, the pine bark beetle was most abundant in stands with many host trees (conifer dominated stands). In the first and second summers after harvest, pine beetle abundance increased exponentially with percent spruce cover and the number of spruce stumps in the stand. Beetles were...
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Synopsis: To date, there is a lack of well-controlled field experiments that disentangle the effects of the intervening matrix from other landscape variables (e.g., patch geography or quality) that might influence animal dispersal among patches. We performed a field experiment to investigate how the movement of a delphacid planthopper (Prokelisia crocea) among discrete patches of prairie cordgrass (Spartina pectinata) is affected by the composition of the matrix (mudflat, native nonhost grasses, and the introduced grass smooth brome [Bromus inermis]). Within each matrix type, marked planthoppers were released onto experimental cordgrass patches that were made identical in size, isolation, and host plant quality....
Synopsis: Riparian buffers, the vegetated region adjacent to streams and wetlands, are thought to be effective at intercepting and reducing nitrogen loads entering water bodies. Riparian buffer width is thought to be positively related to nitrogen removal effectiveness by influencing nitrogen retention or removal. We surveyed the scientific literature containing data on riparian buffers and nitrogen concentration in streams and groundwater to identify trends between nitrogen removal effectiveness and buffer width, hydrological flow path, and vegetative cover. Nitrogen removal effectiveness varied widely. Wide buffers (.50 m) more consistently removed significant portions of nitrogen entering a riparian zone than...
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Conclusions: Habitat associations of prairie rattlesnakes appear to differ depending on whether snakes are hibernating, foraging, or reproducing. Most rattlesnake hibernacula occur within 4 km of a major river, drainage, or coulee, on relatively gentle slopes, but they migrate as far as 25 km away from dens in summer. High road densities present unfavorable habitat conditions for snakes because they are a significant cause of mortality. *Note that this study generated landscape level models with coarse variables, and the thresholds and values used may not be directly applicable to other areas or for site-specific analysis. Thresholds: Most rattlesnake hibernacula occur within 4 km of a major river, drainage, or...
Conclusions:When riparian vegetation is maintained in areas of intensive agriculture, suspended solids levels are generally lower due to reduced in-stream organic production. Sediment deposition in near stream areas and stream bank scour are also reduced when riparian vegetation is present.Thresholds/Learnings:
Conclusions:Over time, native species richness increased slightly, but dropped dramatically after several years of burning. Year-to-year change in community composition was found to be affected by time since fire and fluctuations in growing season temperature and rainfall. Examining successional trajectory showed that the restoration has been most successful at reducing exotic species and increasing species heterogeneity, but has largely failed to increase native species richness at the level of remnant prairies, largely due to interspecies resource competition.Thresholds/Learnings:
Conclusions:The occurence of bull trout in mid-boreal stream is negatively related to two metrics of industrial activity: percent forest harvesting and road density. Bull trout abundance was positively related to elevation, and negatively related to stream width, slope, and levels of forest harvesting.Thresholds/Learnings:Timber harvest on up to 35% or more of individual subbasins is projected to result in the extripation of bull trout from up to 43% of stream reaches, especially those that support high densities of bull trout.
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Synopsis: This document details the Milk River Basin project, designed to produce innovative approaches to multi-species management in Southern Alberta. The Milk River basin contains a variety of ‘sensitive’, ‘at risk’, and ‘may be at risk’ species. The process of prioritizing the landscape for conservation and stewardship was driven by species inventories to identify known locations, and Habitat Suitability Index (HSI) models to delimit suitable key habitat for the 17 selected species. The construction of the models was limited to the available variables and resolution of the databases. For MULTISAR: the Milk River Basin Project area this was the quarter section, the resolution of the Native Prairie Vegetation...
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Synopsis: Preliminary research and observations made by farmers suggest that shelterbelts placed around livestock production facilities may effectively reduce movement of odors emitted by manure to neighbouring properties. Essentially, trees can be 'put to work' to reduce the movement of livestock production odors off-site. An odor-emitting source can include a livestock production barn, manure storage or a farm field where manure is being spread. Shelterbelts have the ability to reduce odor concentrations significantly at or very near the source, which greatly improves the effectiveness of separation distances. There are five ways that treed windbreaks and shelterbelts can reduce the effects of livestock odor...
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Synopsis: This study evaluated the effects of landscape management on the spread of mountain pine beetle colonization in Banff National Park, Alberta, Canada. Researchers used annual aerial survey data and geo-referenced locations of colonized trees that were cut and removed to assess if the area colonized and the spatial extent of pine beetles differed between monitoring and management zones. Pine beetles were allowed to follow their natural course in the monitoring zone, while an extensive eradication program involving cutting and burning colonized trees was established in the management zone. Management resulted in no detectable effect on the scale of the zone. However, at the sub-zone scale, the area affected...
Conclusions: Structurally complex landscapes support more species than simple landscapes, implying that habitat patches in complex landscapes receive a higher diversity of potential colonists from the overall species pool than do patches of the same size and quality in less complex landscapes. Thresholds/Learnings: Synopsis: Structurally complex landscapes support more species than simple landscapes, implying that habitat patches in complex landscapes receive a higher diversity of potential colonists from the overall species pool than do patches of the same size and quality in less complex landscapes. Movement across habitats is a common phenomenon in many species and the spillover of organisms from natural habitats...
map background search result map search result map Area requirements of grassland birds: a regional perspective. Weidemeyer's Admiral A blueprint for sage-grouse conservation and recovery Urbanization of aquatic systems: degradation thresholds, stormwater detection, and the limits of mitigation. Distribution of bark beetle, Trypodendron lineatum in a harvested landscape Effect of management on spatial spread of mountain pine beetle (Dendroctonus ponderosae) in Banff National Park. Short-horned Lizard Pollinators provide economic incentive to preserve natural land in agroecosystems Matrix composition affects the spatial ecology of a prairie planthopper. Wildfire Impacts on nitrogen concentration and production from headwater streams in southern Alberta's Rocky Mountains. Prairie Rattlesnake. Using Shelterbelts to Reduce Odors Associated with Livestock Production Barns. The Milk River Basin Project; Habitat Suitability Models for Selected Wildlife Management Species No. 86. Alberta Species At Risk Report, Alberta Sustainable Resource Development, 2004 Wildfire Impacts on nitrogen concentration and production from headwater streams in southern Alberta's Rocky Mountains. Urbanization of aquatic systems: degradation thresholds, stormwater detection, and the limits of mitigation. Effect of management on spatial spread of mountain pine beetle (Dendroctonus ponderosae) in Banff National Park. Distribution of bark beetle, Trypodendron lineatum in a harvested landscape Matrix composition affects the spatial ecology of a prairie planthopper. A blueprint for sage-grouse conservation and recovery Pollinators provide economic incentive to preserve natural land in agroecosystems Area requirements of grassland birds: a regional perspective. Using Shelterbelts to Reduce Odors Associated with Livestock Production Barns.