The NAWMP uses the period 1970-'79 as a benchmark against which to measure current waterfowl populations. Most Joint Ventures (JV's) under the NAWMP have adopted species population goals equal to the average of the 1970s. In recent years most species have reached or exceeded the numeric NAWMP goals in the PPR, with the notable exceptions of pintails and scaup (Table 4). However even for the species that have apparently achieved target goals, the population response has not been as great as expected based on historical patterns between ducks and precipitation. There is clearly a need for enhanced habitat conservation efforts if target populations are to be sustained.
Table 4. Breeding duck population status and goals for the 10 most common species in the PPR (as stated in the 1998 plan update).
Importance to other wildlife species
The same complexes of wetlands and grasslands that make the PPR the core breeding area for North America's waterfowl also make the region extremely attractive to other migratory species. Besides ducks, geese, and swans, 225 other migratory bird species can be found in the PPR. Recent studies have shown that populations of many of these birds are diminishing at an alarming rate. These include numerous species of shorebirds, wading birds, and grassland songbirds. Included among these are priority species such as whooping cranes, Franklin's gulls, yellow rails, burrowing owls and piping plovers. During spring migration, wetlands are used by Hudsonian godwits, American golden plovers, white-rumped sandpipers, and buff-breasted sandpipers. Shorebirds such as Wilson's phalaropes, marbled godwits, and American avocets are common breeders in prairie pothole wetlands. In areas where large tracts of grassland still exist, priority species such as Baird's sparrows and Sprague's pipits are common.