Restoring one of Canada’s biologically richest locations: Cootes Paradise Marsh

2012-2013 Funding: $2,279,981 total, including $125,000 provided by the Great Lakes Sustainability Fund

Other Project Contributors: Ontario Ministry of Environment and Climate Change, the Royal Botanical Gardens, ArcelorMittal Dofasco, the Hamilton Harbour Remedial Action Plan Office, the Bay Area Restoration Council, the City of Hamilton, the City of Burlington and private donors.

Canada’s largest botanical garden is undertaking an ambitious long-term effort to restore its once biologically rich wetlands and shoreline habitats, thanks in part to support from the Great Lake Sustainability Fund.

The Royal Botanical Gardens is internationally known for its display gardens. It also has extensive marshlands in the 250-hectare Cootes Paradise marsh - one of the most biologically diverse locations in Canada - and lower Grindstone Creek, which flow into Hamilton Harbour in western Lake Ontario. Historically, these marshlands were prime fish nurseries and migratory bird staging areas in western Lake Ontario. By 1980, however, these sanctuaries had completely collapsed, largely devoid of plants and no longer capable of serving as productive habitat for fish and bird species. Key factors in this decline included poor water quality due to the inflow of excessive nutrients and sediments; excessive algae growth resulting from runoffs of fertilizers and urban wastewater; the impacts of non-native fish species, particularly the common carp; and fluctuations of water levels from Lake Ontario water-level controls.

Project Paradise was launched in 1993 as a component of the Hamilton Harbour Remedial Action Plan to address all of these factors, with the long-term goal of having habitats naturally regenerate and become self-sustaining. The initiative includes a wide variety of conservation projects, but the overall success of the project depends on significantly reducing the presence of carp in the wetlands. First introduced into the region in the late 1800s in fish hatcheries, carp had, by the 1930s, become by far the dominant species throughout the Botanical Gardens marshlands. The bottom-feeding and spawning actions of carp can uproot and crush aquatic plants and reduce water quality.

Carp barriers are typically a set of vertical bars about 5 cm apart that restrict the species from entering an area while allowing other species to pass through. They have been established at several locations in the wetlands complex. The Cootes Paradise fishway is the first two-way fishway/carp barrier structure on the Great Lakes and an important site for public education and outreach efforts.

At the same time, native plant species, including cattails, waterlilies and wild rice, have been planted as part of the restoration efforts. Turtle nesting habitat has been re-established in one bay by removing woody invasive species that were shading the site and by mixing up hardened soil to make nesting easier for the turtles. And for all of its long-term focus, the project has had some exciting immediate results, too: in March 2013, a pair of Bald Eagles that had arrived in 2008 successfully hatched young, the first time in more than 50 years that eaglets have hatched on the Canadian shoreline of Lake Ontario.

Consult the following external web site for more information on the Hamilton Harbour Remedial Action Plan.