Pipestone Rocks (MB012)
Lake Winnipeg, Manitoba
Site Description
The Pipestone Rocks are a group of small islands in the southern portion of Lake Winnipeg, Manitoba. They are located near the northern edge of the Hecla / Grindstone Provincial Park; Deer Island is located directly to the south, and Grindstone Point is located to the southwest. The islands, which are comprised of granite rock extrusions filled with bird guano, are devoid of trees and shrubs. The water level around the island can change greatly due to the wind tides that occur on Lake Winnipeg. Since water levels fluctuate greatly from year to year, the size and shape of the islands often changes. During high water years the islands may completely disappear.
Birds
Large numbers of American White Pelicans nest on the Pipestone Rocks. During a 1997 survey there were at least 500 pairs of American White Pelicans present (a thorough survey was not completed because observers did not want to unduly disturb the birds). Subsequent surveys also recorded large numbers, with 713 American White Pelican young being observed during a 1990 survey and 742 nests being observed during a 2012 aerial survey. These surveys likely represented just under 1,500 adults.
Other species that nest on these islands include: Herring Gulls (275 pairs in 1990; 467 pairs in 2012), Ring-billed Gulls (>2,000 nests in some years; 856 in 2012), and Double-crested Cormorants (over 500 pairs in 1990; 878 in 2012).
Conservation Issues
The Pipestone Rocks, which are already within Hecla/ Grindstone Provincial Park, were previously considered as a potential site for provincial Ecological Reserve status, although this nomination was withdrawn prior to 2014. The islands were previously considered for transfer to the federal government, as part of a newly proposed national park. Even as is, the rocks are categorized as Backcountry Land Use within the park, which legally protects them from logging, mining and hydroelectric development.
IBA Criteria Habitats Land Uses Potential or Ongoing Threats Conservation Status
