(52°42’ N; 107°10’ W: Map sheet 73 B/11). Redberry Lake is located in the boreal parkland ecoregion, 56 km northwest of Saskatoon and 13 km east of Hafford. Scientifically investigated by Rawson and Moore in 1938–40 and by Hammer and associates from 1971 to 1988, it is a closed, saline lake, with no outlet. Salinity measured 12g/L in 1926, and 24g/L in 1988; this increase was associated with declining lake depth during drought.
In 1974 the lake had an area of 53.42 km. and a maximum depth of 18 m. The water is very clear. It stratifies thermally every spring as the upper waters warm up while cold water persists below 9 m to 14 m; oxygen depletion occurs only slightly in this cold layer. The salt content of the lake is mainly magnesium, sodium and sulphate. The pH of the water in 1974 was 9.2. Plankton populations (microscopic free-floating organisms) are relatively low. Bottom populations are dominated by chironomids (fish fly larvae) in deep waters, and damsel fly nymphs and the amphipod Hyallel azteca in shallow marginal waters.
In 1940–41 D.S. Rawson stocked the lake with whitefish (Coregonus clupeaformis). Its salinity was then15g/L. The fish grew so rapidly that a commercial fishery was initiated in 1946; but it ceased after 1981 as salinity increased to 20g/L and the fish could not survive. During this period 500,000 kilograms of whitefish were harvested. Redberry Lake was declared a Migratory Bird Sanctuary in 1925, and became a Provincial Wildlife Refuge in 1986. Lake islands are the nesting grounds for white pelicans (Pelicanus erythrorhynchos). California and ring-billed gulls, black and common terns, and double-crested cormorants also nest there and feed in lake waters. The lake is an important spring and fall staging ground for ducks and other waterfowl. White-winged scoters (Melanitta deglandi) use the lake and are being studied by the Canadian Wildlife Service. In 2000 (after nomination by First Nations, local conservation groups, and local, provincial and federal government), UNESCO’s Man and Biosphere Program designated Redberry Lake as the Redberry Lake Biosphere Reserve (See Conservation).
Redberry Regional Park was established on the northwest portion of the lake in 1968. There is a beach area with waters suitable for wading and swimming. A service area was established and a golf course developed. The Saskatoon Sailing Club is based at the lake; recreational boating is important; and many cottages have been built. Proximity to Saskatoon has made this site a prime recreation area.
U. Theodore Hammer