NAWMP on the prairies—18 years of learning and adapting
With the advent of the NAWMP in 1986, biologists were challenged to develop new programs on an unprecedented scale, with the goal of restoring waterfowl populations to the high levels seen in the 1970s. No conservation initiative of this magnitude had ever been contemplated before anywhere in the world.
In the early 1980s there was still much debate about what factors determine prairie duck numbers. New evidence was emerging, however, from both the U.S. Fish and Wildlife Service (USFWS) and the Canadian Wildlife Service (CWS), that pointed toward poor nesting success associated with intensification of agriculture. Wetland loss, while still serious, was no longer judged to be as limiting for most duck species as the loss of nesting habitat. Thus, the waterfowl conservation community began to address the conservation of whole landscapes—wetlands, grasslands, woods, and fields.
Planners were still faced with a wide array of possible conservation actions and no obvious way to choose among them. The approach taken by DU in Canada and its NAWMP partners was first to select target areas for upland cover enhancement based on wetland abundance, which largely determines local duck abundance. Planners then chose among candidate conservation measures by using a modified form of a computer model of mallard production (the "mallard model") developed by USFWS researchers. Canadian planners focused most of their attention on the aspen parklands rather than the more arid grasslands, believing that in most years the parklands would be wetter and thus have greater potential to produce ducks. In the United States, where previous conservation efforts consisted mostly of restoring larger wetlands and purchasing federal waterfowl production areas, planners followed a similar path, but based upon USFWS wetland management districts.
The mallard model was not designed from the outset to plan habitat programs, but rather as an aid to understanding mallard biology. And in the mid-1980s, such models were unable to incorporate information about the spatial arrangements of habitats: For example, how close planted nesting cover is to wetlands or what geometric shape a conservation project might assume. Despite these limitations, the mallard model was then state-of-the-art technology. By using the model to generate estimates of duck production before and after simulated applications of conservation programs, planners chose an array of actions expected to achieve NAWMP duck population goals. This work culminated in the first-ever comprehensive conservation plans for the Prairie Pothole Region.
So, conservation delivery changed and accelerated beginning about 1990 as new U.S. and Canadian federal dollars, matched by DU funds, flowed toward the prairies. Recognizing the huge conservation challenges ahead, the uncertainties about how ducks and people would respond, and the imperative of using funds wisely, DU committed to learning and improving its performance while it delivered NAWMP conservation projects.
With the support of the North American Wetlands Conservation Council, DU launched the ambitious Prairie Habitat Joint Venture Assessment Study in 1993. Scientists from DU's Institute for Wetland and Waterfowl Research followed the fates of more than 3,600 radio-marked mallard hens and more than 16,000 duck nests on 27 25-square-mile study sites in Alberta, Saskatchewan, and Manitoba between 1993 and 2000. The study was designed to determine the effectiveness of the new habitat programs and to test the major assumptions and data used in the planning model. Feedback from this study substantially modified NAWMP conservation programs and spawned development of a second-generation computerized planning tool to help guide decisions about conservation investments.
It turned out that as a planning tool for the parkland region, the original mallard model needed adjustments. In the end, planners decided that a simpler, multispecies model would provide a better solution. Fortunately, much of the research needed to build the new planning tool had been accomplished during the assessment study.
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