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How ESSA has successfully used Decision Analysis to overcome challenges in multi-objective resource management problems Developed by ESSA Technologies.

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Presentation on theme: "How ESSA has successfully used Decision Analysis to overcome challenges in multi-objective resource management problems Developed by ESSA Technologies."— Presentation transcript:

1 How ESSA has successfully used Decision Analysis to overcome challenges in multi-objective resource management problems Developed by ESSA Technologies Ltd. General overview January David Marmorek, Calvin Peters, Ian Parnell, Clint Alexander

2 Common challenges in resource management
Getting stakeholder groups to agree on a course of action, given multiple values and objectives Getting scientists to agree on which uncertainties most critically affect management decisions, and what decisions are most robust to these uncertainties Evaluating the costs and benefits of adaptive management - is it worth it?

3 How decision analysis can help with these challenges
It provides a toolbox for handling multiple objectives / values, and analyzing tradeoffs among these objectives It systematically analyzes the impacts of uncertainties on decisions It can be used to evaluate the ability of Adaptive Management experiments to improve decisions It provides a helpful way to integrate many techniques employed by managers and scientists (i.e. models, interactive workshops, sensitivity analysis) into products that better clarify management decisions

4 Three examples Getting scientists to agree: PATH
Getting stakeholders to agree: Cheakamus Evaluating adaptive management: Keenleyside

5 PATH: Decision Context
Multiple historical changes in Columbia and Snake River ecosystems and fisheries management practices Endangered species listings for Snake River salmon populations Multiple hypotheses and uncertainties held by different groups of scientists Duelling models representing these hypotheses and uncertainties Best management policies for species recovery?

6 PATH: Washington State, US

7 Decision Analysis: 8 elements
1. List of alternative management actions 2. Management objectives composed of performance measures (to rank management actions) 3. Uncertain states of nature (different hypotheses) 4. Probabilities of those states (to account for uncertainty); 5. Model to calculate outcomes of each combination of management action and hypothesised state of nature; 6. Decision tree; 7. Rank actions based on expected value of the performance measures; and, 8. Sensitivity analyses.

8 Decision Analysis: Basic Elements

9 PATH Decision Tree

10 Benefits of decision analysis in PATH
Allowed evaluation of multiple hypotheses for 14 uncertainties - scientists did not have to agree! Only 3 of these turned out to make a difference to the decision - created a common focus for AM, research Preferred actions were those which were most robust to the critical uncertainties (drawdown A3) Sensitivity analyses defined how much belief you would have to have in a given hypothesis to change decision

11 Recent Publications on PATH
Marmorek, David R. and Calvin Peters Finding a PATH towards scientific collaboration: insights from the Columbia River Basin. Conservation Ecology 5(2): 8. [online] URL: < Deriso, R.B., Marmorek, D.R., and Parnell, I.J Retrospective Patterns of Differential Mortality and Common Year Effects Experienced by Spring Chinook of the Columbia River. Can. J. Fish. Aquat. Sci. 58(12) Peters, C.N. and Marmorek, D.R Application of decision analysis to evaluate recovery actions for threatened Snake River spring and summer chinook salmon (Oncorhynchus tshawytscha). Can. J. Fish. Aquat. Sci. 58(12): <same web site as above> Peters, C.N., Marmorek, D.R., and Deriso, R.B Application of decision analysis to evaluate recovery actions for threatened Snake River fall chinook salmon (Oncorhynchus tshawytscha). Can. J. Fish. Aquat. Sci. 58(12): <same web site as above>

12 Cheakamus WUP: Decision Context
British Columbia Hydro, Water Use Planning: Stakeholder driven multi-objective consultation / decision process. No formal incorporation of uncertainty as for PATH Emphasis: values, objectives, performance measures, trade off analysis (DA steps 1, 2, 5 and 7). Used PrOACT approach (Smart Choices, Hammond et al 1999)

13 Cheakamus WUP: Process
WUP Steps

14 Cheakamus WUP:Decision Problem
Select operating alternatives for Daisy Lake Dam that: 1) recognize multiple water uses in the Cheakamus and Squamish Rivers, and 2) achieve a balance between competing interests and needs.

15 Cheakamus WUP:Objectives and PMs
Power First Nations Recreation Flooding Fish Aquatic Ecosystem

16 Cheakamus: WUP Alternatives
Consultative Committee specifies operating alternatives for Hydro operations model (AMPL). Basic constraints: minimum flow at Brackendale gauge, minimum dam release. AMPL model produces 32 water years of flow data for these control points Flow data and other models used to calculate performance measures. Performance measures summarize consequences of alternatives for objectives.

17 Cheakamus WUP: Consequences

18 Tradeoffs (or not) Win-Lose Win-Win

19 Cheakamus WUP: Filtering
Use PMs to Eliminate clearly inferior alternatives. Drop insensitive PMs (e.g., rafting). Drop Objectives that don’t help the decision (e.g., flooding). Tradeoff analysis: Even Swaps Elicit values behind decisions (e.g., rating exercises) Develop new alternatives to address concerns (e.g., chum spawning vs. rainbow trout rearing).

20 Keenleyside Problem : Increased egg mortality from dam operation
Flow during spawning Flow during incubation  stage Proportion eggs in de-watered area Risk Biological flows too high reduce productive capacity, may drive population towards extinction Economic smaller flows may reduce de-watering mortality but reduce potential $ and operational flexibility

21 Problem II: Uncertainty True whitefish recruitment dynamics?
Given typical egg mortality, LARGE differences in abundance associated with these curves No reliable baseline information

22 Stage 1 - Decision Analysis w current uncertainty

23 Stage 1 Results: Current Uncertainty
Objective: Maintain “least cost” whitefish population nearest to or greater than 45,000 adults

24 Stage 2 - Simulated learning from flow experiments and monitoring
Uses same model and uncertain components but... Actions are now alternative experimental flow regimes + monitoring programs Assume a true relationship for population dynamics with process error

25 What would you change if you knew the “truth”
What would you change if you knew the “truth”? If population insensitive, then maximize power revenues (85 kcfs) If population sensitive, then minimize biological risk (~60 kcfs) 10 5 2.5 7.5 $Cnd mil Max. potential power revenues (per yr)

26 Example Stage 2 Results: Good monitoring is critical for differentiating hypotheses; flow manipulation had less effect than expected.

27 AM can “pay for itself”

28 Is AM and monitoring worth it?
“Yes” If New information leads to choice of a different management action that better satisfies a particular objective, or rigorously confirms that current management action is appropriate.

29 No definitive “yes/no”
Under AM practitioners control Can evaluate implications using decision analysis? Factor Management objective (fish vs. power $) Ability to do well designed experiments Initial level of uncertainty in alternative hypotheses Magnitude of natural variability in the system What “truth” really is Inherent sensitivity of best action to uncertainty Yes Maybe No No (can’t know without doing the experiment) Yes

30 General Conclusions Value of AM potentially large
Whether to proceed depends on “the kind” of system you are in (i.e. previous factors) Decision Analysis is very helpful for evaluating these benefits Determine which uncertainties have strongest effect on choice of “best” management decision Decisions more robust to uncertainties (reduces risk - integrates broader range of possible outcomes included) Include new information as revised probabilities on hypotheses

31 Decision Analysis - Summary


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