Atlantic coast joint venture waterfowl implementation plan
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1 – Area importance determined from range map in Bellrose (1976) 2 - Area importance determined from expert opinion 
Figure 6.1. Waterfowl Conservation Regions (WCR) as delineated in 2004 Update of the North American Waterfowl Management Plan. Within the ACJV, these regions are the same as Bird Conservation Regions (BCR) with the following exceptions. Southern boundary of WCR 30 is north of revised southern boundary of BCR 30 (i.e., WCR 30 excludes southern extent of Chesapeake Bay). WCR 27 is subdivided into three regions unlike BCR 27. The ACJV recognizes WCR 69 pursuant to FWS Southeastern Region internal memo. there is no consensus on how migratory or wintering waterfowl populations and habitat relate to the breeding objectives of NAWMP. The NAWMP National Science Support Team (NSST) has therefore recommended an interim method that uses a combination of MWS and harvest data to proportionally allocate the continental objectives between the various joint ventures. An evaluation of these methods indicates that this allocation works reasonably well for most duck species (exceptions include: Mottled Duck, whistling-ducks, Blue-winged Teal and Wood Ducks) but not for geese in general (M. Koneff, pers. comm.). Implicit in such an endeavor is the assumption that local or regional actions are hierarchical in nature and can be aggregated to, in this case, a larger spatial scale. Although intuitive, there is no clear consensus on the functional form of such a relationship. In the absence of a clear analytical solution to the problem, the NSST reviewed alternative approaches and reached consensus in November 2003. As the official technical advisory committee of NAWMP, the NSST recommendations are being followed by most of the non-breeding joint ventures in North America. The method being recommended by the NSST is a three-step approach that allows non-breeding joint ventures to “step-down” the continental population goals into regional goals that can be used for planning habitat delivery programs. The NSST recommends that these numbers not be used as a performance metric per se, but only for baseline planning purposes. As such the first step of the process is to determine the proportion of the continental population goals a joint venture might be responsible for over-wintering. The second step is to explicitly state the assumptions being made as to the regional requirements of waterfowl, resource availability and assess trends of the resource. Lastly, joint ventures need to evaluate the validity of the assumptions made in the second step. The NSST recommendations only concern the first step of this process: determination of the proportional allocation of continental objectives to the regional scale. The NSST is advocating the use of MWS and county level, species specific harvest data as a reasonable first approximation of the wintering distribution of waterfowl. It was noted that use of this approach incorporates all the potential biases that have been identified regarding the MWS data (Heusmann, Eggemann and other citations here). Although there are local data sets that might overcome some of these limitations, there is no other data set that covers the entire joint venture that could be used as a surrogate. Likewise, the county level-harvest data contain their own biases but lack of an alternate surrogate argues in favor of their use. As a first approximation of objectively determining how many acres the ACJV needs to protect, restore or enhance, we used the NSST approach to calculate what the ACJV Waterfowl Technical Committee has termed a Wintering Habitat Capability Index (WHCI; see Appendix B for results of this exercises). After a thorough review of this approach and the results obtained for the ACJV, a sub-committee of the Waterfowl Technical Committee (WTC) reached the consensus that there were too many unanswered questions from this approach to use it to set habitat goals within the ACJV. Specifically, this sub-committee noted that although using the NSST approach attempts to integrate conservation efforts in the ACJV with NAWMP goals using a rigorous, science-based approach there where over-riding issues that warrant caution at this time. Specifically, they believed this method:
Until consensus can be reached on how to convert the WHCI into an estimate of how much habitat needs to be protected, restored or enhanced we will rely on expert opinion from each partner state’s Waterfowl Technical Committee (WTC) Representative. Thus, we asked for an estimate of the acres (wetlands and associated uplands) that still need to be protected, restored or enhanced in each Waterfowl Focus Area (see Section 7.2 for Focus Area definition) for wetland and waterfowl conservation. These estimates were to be based on an individual’s knowledge of the area, an assessment of waterfowl habitat needs in that focus area, areas that have already been conserved there, and GIS tools if available. For each Waterfowl Focus Area, a map showing National Wetland Inventory and topographic features including a summary table of the area by wetland class was reviewed by each state’s ACJV Waterfowl Technical Committee member. If there are acres outside of the focus areas that needed to be protected, restored or enhanced for waterfowl conservation, those were to be included as a separate total. The total of these focus area and state acreage goals for all states will constitute an interim acreage goal for the ACJV (Table 6.8). Based on this information, going forward, ACJV partners need to conserve, through protection, restoration or enhancement, more than 638,000 ha (>1,577,000 acres) of wetlands and associated uplands to meet our commitment under the NAWMP. As the ACJV moves forward, our desire is to embrace a more biologically sound approach to estimating population-based habitat goals. The diversity of habitats and large spatial scale of the ACJV currently preclude the use of energetic models used by other non-breeding joint ventures as the ACJV currently does not have the necessary information to parameterize the model for all habitat types (Conroy and Gordon, 1990). In addition, adopting this approach relies on the unproved assumption that food is the limiting factor for waterfowl within the ACJV. Future research in the joint venture will focus on determining limiting factors and testing assumptions to allow for habitat models and population-based habitat objectives. These efforts will also allow for an evaluation of the effectiveness of conservation actions on these populations. Table 6.8. Interim habitat objectives for the Atlantic Coast Joint Venture based on the expert opinion of Waterfowl Technical Committee Representatives. Objectives are based on Representative’s professional knowledge of local wetland and waterfowl conditions. See footnotes for methodology used by individual states to estimate these interim objectives.
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