Cumulative Impact Management:
Cumulative Effects Case Studies
Presented by:Salmo Consulting Inc. andAXYS Environmental Consulting Ltd. in association with Diversified Environmental Services GAIA Consultants Inc. Forem Technologies Ltd.
May 29-30, 2003
IntroductionA component of the Cumulative Impact Management (CIM) frameworkDetailed evaluations in Blueberry and Sukunka Case Study areasDocument land use, fish and wildlife trends and identify apparent thresholdsTest CIM indicatorsEvaluate utility of readily-available dataSimulate future resource trendsIdentify implementation issues
Case Studies: Blueberry Area2,690 km2 area northeast of Wonowon50 year multi-sector development history Boreal Plains Beatton River watershedOverlaps 4 RMZ in FSJ LRMP areaJedney Enhanced Resource MgmtAgriculture/SettlementGrazing ReserveAlaska Highway Corridor
Case Studies: Blueberry Area
Case Studies: Sukunka Area1,200 km2 area south of Chetwynd20+ year multi-sector development history Rocky Mountain FoothillsSukunka River watershedOverlaps 6 RMZ in Dawson LRMP areaSouth Peace (Burnt River) Enhanced Resource Mgmt zoneSukunka and Pine River Corridor Special Mgmt zones
Case Studies: Sukunka Area
Case Studies: MethodsDeveloped GIS database Forest coverGovernment digital dataLand useGovernment TRIM digital dataHistorical air photosResource trendsFish and wildlife surveys and reportsWildlife harvest
Case Studies: TrendsLand Use Access corridors (roads, trails, seismic lines, pipelines, power lines, rail lines)Clearings (wells, facilities, cut blocks, agricultural, mines, residential)Cumulative Impact Indicators (access density, stream crossing index)ResourceFocus wildlife speciesMoose, woodland caribou, elk, grizzly bearWildlife habitat suitability ratings 4 class system based on forest cover and ageCumulative Impact Indicators (core area, patch size)
Case Studies: TrendsEvaluated relationship between habitat and land use trends and wildlife population index (harvest success) Future trends in Blueberry areaForecast using existing ALCES model100 years: 1950 to 2050
Case Studies:Future Scenarios ..Forecast changes from natural processesNatural disturbance regime (fire and natural succession)Forecast changes from human disturbance Land use trends extrapolated from past historyLow, Moderate, High growth scenariosSimulation (what-if?) modelling for combined changesWildlife habitat effectiveness Variable effect management methodsBest Practices,
Blueberry Case Study:Clearing Trends ..
Blueberry Case Study:Access Trends ..
Blueberry Case Study:Moose Natural Disturbance ..195020002050
Blueberry Case Study:Moose Combined Disturbance ..205020001950
Blueberry Case Study:Moose Population Trends..Moose harvest variable but generally decliningHarvest influenced by environmental factors, regulation changes, and improved access (OHVs)Gradual decrease in harvest success Success inversely related to level of disturbanceSuccess directly related to amount of core (undisturbed) habitat
Blueberry Case Study:Moose Population Trends..Increased cumulative impact risk ..Most moose now inhabit edge areas where disturbance and human mortality risk is higherSteady, slow loss of habitat to permanent infrastructure . not translated into population declinesPopulation stable between 1982 and 1998Combined disturbance in range of natural variabilityRestrictive harvest restrictionsIncreased availability of early seral stagesPossibly reduced predation
Blueberry Case Study:Caribou Natural Disturbance ..205020001950
Blueberry Case Study:Caribou Combined Disturbance ..205020001950
Blueberry Case Study:Caribou Population Trends..Population numbers low Initially limited by natural fire patternsRegional populations significantly lower than historical levelsCaribou presence occasional by early 1980sIncreased cumulative effects risk Combined disturbance outside range of natural variabilityWoodland caribou unlikely to persist in Blueberry study area
Understanding the Landscape: Case Study FindingsReadily-available data limited analyses Access density and core area indicators both statistically related to moose and elk population indicesPredictive power equivalent to more detailed and costly habitat indicatorsIncreased cumulative effects risk not translated into population declines for these speciesAll indicators suggest that probability of woodland caribou persistence in Case Study areas is lowBoth natural and human causes
Understanding the Landscape: Case Study FindingsALCES simulations provide valuable historical and future insightsPublished access density relationships may not apply directly to Northeast BC No clear thresholds evidentComparatively low population and human activityResearch in developed landscapes needed to document regional fish and wildlife response