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Conservation Planning for Shorebirds
Breeding Shorebirds
Populations and ranges of several species of breeding shorebirds are shrinking as wetland and grassland habitats are lost in the Prairie Pothole Region. Unfortunately, little information exists to guide landscape-level planning and management of these species. Since 2004, a team of dedicated volunteers has monitored breeding shorebirds throughout portions of North Dakota, South Dakota, and Montana (Figure 1) to help guide shorebird conservation efforts in the Prairie Pothole Region.
Prior to instituting the survey, the HAPET office spent two years collecting and analyzing data to evaluate survey techniques, including effects of roadside sampling, daily and seasonal timing, and habitat characteristics. Based on evaluation results, roadside surveys were designed to maximize detection of breeding shorebirds per unit effort, monitor population trends, and provide data suitable for development of spatial models that predict shorebird occurrence based on associations with landscape characteristics.
Figure 1. Location of 49 breeding shorebird survey routes in the Prairie Pothole Region of South Dakota, North Dakota, and northeastern Montana.
The number of birds detected on surveys varies markedly among routes. For example, in 2004 zero shorebirds of any target species were detected on two routes in the black desert of eastern North Dakota, whereas dozens of individuals of several species were found on routes located in areas of better habitat. However, sampling of poor habitat as well as good habitat is critical to understanding landscape-level habitat selection, and enables development of predictive models (Figure 2) that can be used to guide conservation.
Figure 2. Predicted landscape suitability for Willet in the Prairie Pothole Region of South Dakota (left) and Wilson’s Phalarope in the Prairie Pothole Region of North Dakota (right) based on 2004 Breeding Shorebird Survey data. Models are based on geographic location and landscape characteristics (e.g., amount of wetlands and prairie) within 800 m of sample points. Landcover data in maps has 30m X 30m resolution.
Unlike many bird surveys that are designed only to document changes in populations, the shorebird survey was designed to monitor populations and provide direction for conservation actions. The primary purpose of developing the maps shown in Figure 2 is to identify landscapes of high importance to shorebirds breeding in the Prairie Pothole Region. Waterfowl conservation efforts in the area, which are funded largely by Duck Stamp dollars, are guided by similar models and have resulted in the protection, restoration, or enhancement of nearly 6 million acres of habitat, with substantial benefits for non-game species. We hope to use conservation planning models such as those shown above to provide greater benefits for shorebirds from expenditure of Duck Stamp dollars, as well as strengthen our ability to attract non-waterfowl money targeted for shorebird conservation.
Data collected on the shorebird surveys are essential to these planning efforts, and the shorebird surveys would not be possible without the assistance and cooperation of many people. Please contact Neal Niemuth if you are interested in running a breeding shorebird survey route. Routes are 25 miles long, require about 4 hours to run, and are run once in late April or early May and again in late May or early June.
Migrant Shorebirds
The numerous small wetlands in the Prairie Pothole Region are also of critical importance to migrating shorebirds. Because of their small size, dispersion, and dynamic nature, few individual wetlands in the Prairie Pothole Region host large concentrations of migrant shorebirds. Instead, shorebirds migrating through the Prairie Pothole Region are widely dispersed, with small numbers of birds at stopover locations that can vary among years depending on water levels.
We evaluated shorebird use of 1,181 temporary and seasonal wetlands within agricultural fields in the Drift Prairie physiographic region of North Dakota over a 10-week period in spring of 2001. A total of 4,050 shorebirds of 25 species were observed on sampled wetlands. Shorebirds selected temporary wetlands that had water present during multiple visits, little emergent vegetation, large perimeters, and other wetlands in the surrounding landscape. Shorebirds were less likely to use wetlands showing evidence of drainage. Observed use of wetland basins suggests that small wetlands in the Prairie Pothole Region host millions of migrant shorebirds each spring. Continued existence of many of these wetlands may be threatened by a recent U.S. Supreme Court ruling that removed federal protection from certain isolated wetlands. Our results show the importance of current wetland protection provisions such as “Swampbuster” and other conservation practices of the United States Department of Agriculture Farm Program.
For more information, contact
Neal Niemuth
US Fish and Wildlife Service
Region 6 Habitat and Population Evaluation Team (HAPET)
3425 Miriam Avenue
Bismarck, ND 58501
701-355-8542
Niemuth, N. D., M. E. Estey, R. E. Reynolds, C. R. Loesch, and W. A. Meeks. 2006. Use of wetlands by spring-migrant shorebirds in agricultural landscapes of North Dakota’s Drift Prairie. Wetlands (in press).
