The Coteau lakes (East and West Coteau lakes) are located just north of the Montana border about 11 km south of Minton, Saskatchewan. A narrow band of native grassland surrounds these saline lakes. While the borders of the lakes are steep and undulating, the surrounding plateau is flat and mostly cultivated. There is one large dam on West Coteau Lake and four smaller dams on East Coteau Lake. These dams help to maintain water levels, especially in the East Coteau Lake. A sodium sulphate mine is located on the shore of East Coteau Lake.
The Coteau lakes often support a significant population of the globally vulnerable and nationally endangered Piping Plover. In six surveys that took place between 1986 and 1996 an average of 21 plovers per year (1.2% of the Canadian prairie population) nested along the shores of the Coteau lakes . During the 1991 international census, a high of 30 plovers was found here, although in other years (when the water levels are high) the species can be absent, or present only in small numbers. The 1996 International Piping Plover Survey recorded 5,913 plovers across the entire breeding range of this North American species. The largest population is located on the northern Great Plains. In 1996, 1,687 Piping Plovers were recorded in the Canadian portion of this population, with 24 of these on East Coteau Lake.
About three-quarters of the lake basins are designated as critical Piping Plover habitat (used by one or more pairs of plovers with a reasonable expectation of repeat use). The designation protects the shoreline, to the high water line, from development under the provincial Wildlife Habitat Protection Act. These protected sections lie west of the dam on East Coteau Lake, and east of the dam on West Coteau Lake).
Drought is a frequent phenomenon of the region. The relationship between drought and Piping Plover productivity has not been clearly established. On the one hand, higher salinity levels lead to fewer plants along the shoreline, a situation preferred by Piping Plovers. On the other hand, too little water is also not favourable for plovers.IBA Criteria Habitats Land Uses Potential or Ongoing Threats Conservation Status