Redberry Lake, named for the profusion of buffalo berries (Shepherdia genus) that grow in the region, is situated in north-central Saskatchewan near the village of Hafford. It is a large, saline lake typical of Saskatchewan's Parkland Region. Historically, water levels were recorded at about 515 m, whereas today's water levels are about 507 m. As a result, the shoreline has been reduced by about 36 km, the area of its islands reduced by 250 ha, and its overall area reduced by about 2,430 ha. At present, the lakes area is 5,610 ha, and includes four islands (with a combined area of about 85 ha). The islands - Pelican, Gull, Old Tern and New Tern - are (or in some cases were) used by nesting colonial birds. The names of these islands, however, do not now reflect the species nesting there. American White Pelicans used Pelican and Gull Islands in 1972, but by 1996 they had relocated to New Tern Island, an island which until recently (up to 1957) was submerged.
In 1991, 524 pairs of American White Pelicans were censused on the islands in Redberry Lake. In 1996, however, the number of nesting pelicans had increased to 1,060 pairs. Based on recent population estimates, these numbers represent about 1 to 2% of the world's American White Pelican population.
Historically, Redberry Lake has also supported nationally significant numbers of the globally-threatened, nationally-endangered Piping Plover. As many as 41 birds were recorded in both 1984 and 1985. In 1991, the International Piping Plover survey recorded 21 birds. In recent years, however, the number of plovers observed has dropped to only four birds in 1996.
During extensive studies completed in 1986, about 400 pairs of nesting White-winged Scoters were recorded on the Lake. It has been suggested that this is the world's single largest breeding concentration of this species. About 215 birds have recorded in the vicinity of the lake.
The lake has been designated a Federal Migratory Bird Sanctuary since 1925, and the islands as Provincial Wildlife Reserve since 1970. In the early 1970s the area was also identified as a candidate representative natural area under the International Biological Programme. In addition, upland habitat (920 ha) has been protected under the provincial Critical Wildlife Habitat Protection Act. The lake and associated uplands are also part of the Provincial Representative Areas Network (RAN).
In recognition of the significance of the area, provincial laws prohibit the use of boats within 100 m of the nesting islands. The Rural Municipality of Redberry has also passed zoning regulations that protect portions of the lake from further development. And the Redberry Pelican Project (RPP) has requested that boaters refrain from entering an advertised 1 km buffer zone around the nesting islands.
Threats exist, even with the above recognition. These include: potential disturbance of colonial waterbirds, scoters and Piping Plovers by boaters; loss of nesting islands through declining water levels; increased salinity due to declining water levels, which may in turn affect primary productivity and ultimately use by birds; and loss of former lake bed to adjacent patented land through the "Law of Accretion".Catégories ZICO Habitats Usages Menaces Potencielles ou Existantes Status de Protection