Colorado State University, Fort Collins, CO
18-19 April 2000
Present: Leigh Fredrickson, Dave Hamilton, Murray Laubhan, and Rick Sojda

• local consequences on the wetland:
• if recommendation from montane wetlands module, then assume positive consequences
• if user entered decision, then evaluate consequence [not current capability]
• local consequences on swans:
• if dry in Spring, then negative consequences on breeding; but it may still be good (or better) Fall or Winter foraging habitat later that year
• [if dry in season X, then always negative consequences for season X]
• flyway consequences on wetlands
• no consequences directly
• effect is through changed swan distribution, e.g., due to increased foraging and potential habitat depletion
• flyway consequences on swans
• factors needing to be considered: precipitation, wetland conditions, season, population trends (e.g., number of cygnets, Canadian production), tundra swan production
• output variables:
• number of swans at each of the other sites
• overall distribution of swans
• condition of swans

• during breeding season they will go elsewhere in the Tri-state with satisfactory conditions (good foraging)
• more likely to go:
• North during Summer
• to closest wetland
• to best habitat (wetland conditions and precipitation)
• least disturbed
[above concepts may not be "considered" by swans in the order]

1. go to closest area
• if good, stay
• if poor, reapply the rule from new area
2. redistribute based on cross-seasonal proportion (for next season) --e.g., 40%, 60%

then, for each new area,
• if good habitat, stay
• if poor habitat, reapply the rule from the new area
3. redistribute based on cross-seasonal proportion (for next season) --e.g., 40%, 60%

then, for each new area,
• if good habitat, stay
• if poor habitat, reapply the rule based on combination of evidence as described by the proportions from new area and the old area

For # 2 and 3, if only one bird or a few pairs, then use highest proportion; if ties in proportion, use closest area.

The following discussion relates to the four simulations as delineated in the project plan.

Simulation #1 - management decisions on areas; input by managers, then what other consequences. Should is be addressed by looking at one step of a redistribution of swans or as a final redistribution of swans.

Simulation #4 - management decisions on optimal set as determined by the system. Essentially, this is similar to simulation #2, but then you have the consequences of changing one decision (management action).

For simulations #1 and #4, one looks at a single decision and propagates the consequences as a final distribution of swans.

Simulation #3 - star with some decisions by manager and generate the best remaining solution. Essentially, is the similar to simulation #2, but with some additional constraints (management actions).

Simulation #2 - generate optimal solution.
 

•  effects on wetlands are always positive, by definition from the wetlands expert system
•  all long term effects are always positive, by definition from the wetlands expert system
•  effects on swan use of wetlands and on swans are always positive under medium water scenarios
•  effects on swan use of wetlands are always negative under low and high water scenarios
•  effects on swans are always negative under low and high water scenarios if alternate habitat is not available
•  effects on swans are always neutral under low and high water scenarios if alternate habitat is available

• We need to know how many birds will arrive on wintering area and when. But, the number of birds arriving may be so insignificant when dealing with trumpeter swans, that the amount habitat needed may also be very small.

• Over long haul, we need to ensure they breeding pair will have good habitat.

• In the suite of habitats in the region, we may need to know what percentage is deteriorating.

• We likely don't want all habitats having management capabilities, in the same phase of the wetland successional cycle.

• We need to consider benefits to all wetland birds, not just swans.

• All long-term concerns outweigh all short-term concerns.

• The linkage among areas may not be within life history events but rather between life history events.

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