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U.S. Prairie Pothole Joint Venture
Implementation Plan

Evaluation of Prairie Pothole Joint Venture

The PPJV potential contribution to the NAWMP continental objective of 62 million breeding ducks is significant.

In 1989, the PPJV Management Board adopted the following waterfowl population objectives:

Right Arrow Bullet        Accommodate an average of 6.8 million breeding ducks,
Right Arrow Bullet        Accommodate an average of 1.2 million breeding mallards,
Right Arrow Bullet        Accommodate an average of 1.1 million breeding pintails, and
Right Arrow Bullet        Contribute 13.6 million ducks to the fall flight.

The NAWMP recommended a nesting success of 50 percent for the PPR. Upon careful review, the PPJV's Waterfowl Technical Committee (WTC), concluded that, at least for the U.S. portion of the PPR, this rate of nesting success was unrealistic, and unlikely to be achieved.

Consequently, in 1991, based on advice and recommendations from the WTC the PPJV Management Board modified those objectives to include a recruitment rate of 0.6, with no area under management for breeding waterfowl having a rate below 0.49. While the PPJV breeding duck objective currently remains the same, the 0.6 recruitment rate required that the fall flight objective be adjusted to 9.5 million ducks.

An evaluation plan has been approved by the Management Board and by the NAWMP Committee to evaluate accomplishments and guide future management. The PPJV evaluation plan consists of three components:

Right Arrow Bullet        Monitoring
Right Arrow Bullet        Assessment
Right Arrow Bullet        Directed Studies


Monitoring is "the process of assimilating status information on habitat and populations." It measures whether population objectives have been achieved through application of management strategies. This is done by:

Right Arrow Bullet        tracking or tabulating management practices (inputs) applied
Right Arrow Bullet        estimating duck populations or their parameters (outputs), and
Right Arrow Bullet        establishing land-use (landscape) trends.

When applied in conjunction with a strategic plan, monitoring provides feedback on whether a management practice(s) has achieved expected recruitment rates. This information then provides guidance for adjusting and making future management decisions.

PPJV Objective 1 is stated in terms of duck populations and recruitment rates. Monitoring is critical for adjusting or refining management strategies. Monitoring uses existing institutions, personnel, and operations. On-going programs of monitoring, e.g., nest success, breeding populations, annual production and survival, breeding bird surveys, and surveys of habitat conditions are adequate as designed for current data needs.

The Population and Production Estimates System (PPES) will be used to monitor breeding pair populations and estimate recruitment. The PPES consists of randomly located Four-Square-Mile (FSM) plots on which duck populations, wetland information and wetland associated wildlife population information are recorded annually. Also, non-wetland habitats are monitored at 5-year intervals. This system is operational in most of the PPJV.

The Continental Evaluation Team's (CET) draft "Non-waterfowl Evaluation Proposal" suggests coordinated monitoring with entities specializing in non-waterfowl species. The PPJV's monitoring efforts will be coordinated with, among others:

Right Arrow Bullet        Partners in Flight
Right Arrow Bullet        Wetlands for the Americas
Right Arrow Bullet        Service/NBS Breeding Bird Survey
Right Arrow Bullet        Iowa Cooperative Fisheries and Wildlife Research Unit

Research findings show that predation is the most important factor depressing waterfowl production. Therefore, expansion of predator surveys is essential for designing waterfowl management strategies.

The evaluation plan uses FSM sample plots to monitor habitat conditions and trends. Sample plot information will be updated at 5-year intervals, and habitat conditions and trends will be compared over time.


While monitoring provides input for certain waterfowl population parameters, detailed assessment tests key assumptions about nesting effort and success, cover attractiveness, brood survival, and hen survival.

Assessment will test these parameters on six sites (3 treatment, 3 control), using two sites per year for 3 years, beginning in 1996. Initial assessment study sites will include CRP lands, and habitat programs with the highest cost, or of greatest predicted importance. Landscapes proposed for study will contain enough of the most important cover types to guarantee meaningful sample sizes of nests.

Data-based estimates of actual numbers of breeding pairs of mallards in the spring and the number of ducklings fledged to the fall flight, compared to final model output, will provide the information necessary to validate and update the Mallard Production Model (MPM) performance. For each study area, estimates will be provided for:

Right Arrow Bullet        Breeding pairs
Right Arrow Bullet        Cover attractiveness
Right Arrow Bullet        Nest success
Right Arrow Bullet        Breeding effort
Right Arrow Bullet        Brood and duckling survival and
Right Arrow Bullet        Summer hen survival.
Two study sites (1 treated, 1 control) per year would be operational in 1996, another two in 1997, and a final two in 1998. First-year costs are estimated at $644,000. Second and third year costs at $494,000 apiece. Total assessment costs are estimated at $1,632,000 for six sites over a 3-year period.

About one-half the annual assessment costs should be a project cost. While not every project would be subjected to assessment, funds would be pooled and expended on selected assessment sites. As assessment efforts proceed, some redirecting of state, Federal, and private research toward PPJV assessment would be possible.


Directed studies (research and development) will fill knowledge gaps or provide new management tools. The Management Board will act as a clearing house for setting directed studies priorities.

To be high priority, directed studies should:

Right Arrow Bullet        Contribute to practical and timely solutions
Right Arrow Bullet        Establish time frames and expected products
Right Arrow Bullet        Avoid duplication of current research
Right Arrow Bullet        Redirect management strategies quickly
Right Arrow Bullet        Address more costly management strategies
Right Arrow Bullet        Address methods that produce larger numbers of ducks
Right Arrow Bullet        Maintain reasonable costs


In addition to annual reports, the PPJV Technical Committee will prepare a formal 5-year report. That report will precede by one year, the NAWMP's 5-year update. This allows for major strategy adjustments based on monitoring, assessment, and directed studies findings for PPJV Implementation Plan revisions.
Previous Section -- Financing PPJV Implementation Strategies
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Next Section -- Appendix A — PPJV Organization and Responsibilities

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