Northern Prairie Wildlife Research Center
Saskatchewan Wetland Conservation Corporation, Room 110, 2151 Scarth Street, Regina, SK, S4P 3Z3 Canada
Agricultural activities have significantly reduced the amount of upland habitat available for nesting ducks. Much of this loss has been the margins associated with wetlands. The main objective of the North American Waterfowl Management Plan (NAWMP) is to restore waterfowl populations by addressing this problem. This study estimated the percentage of wetland loss in Saskatchewan from the late 1940's to the present. We examined 84 quarter-sections comprised of 23, 20, 18, 12, and 11 quarter-sections at Wadena, Redvers, Saskatoon, Thickwood Hills, and Melfort, respectively, by comparison of wetlands on aerial photographs from 1947 to date.
A total of 2,469 wetlands were counted on the old photos for a mean of 29.4/quarter-section. On the recent photography, 2,314 wetlands were counted for a mean of 27.5/quarter-section. Overall, we found a 6% loss of wetland basins. Thickwood Hills had the highest loss (29%) while Redvers had a 5% increase. The three other regions showed 7, 7, and 16% losses. Ninety-two percent of wetlands found on the ground were located from the photos. Most of the wetlands missed were small temporary basins and some roadside wetlands.
We concluded that although the actual permanent loss of number of wetland basins or depressions caused by drainage or filling between the 1940's and early 1990's may only be in the order of 10%, functional loss (or more transitory impacts) particularly due to cultivation, may easily exceed 50%.