The province and Ducks Unlimited Canada unveiled a plan Friday to clean up Delta Marsh by going after carp, an invasive fish that rips out sensitive plants when feeding and spawning.

The $3.5-million partnership will see special screens installed at access points to the marsh from Lake Manitoba to keep carp out during the spring, but allow other smaller fish like pickerel and yellow perch to come and go without interfering with their spawning.

Conservation and Water Stewardship Minister Gord Mackintosh said the restoration will improve its natural function to filter out nitrogen and phosphorus that would otherwise flow into the province's waterways.

The announcement of the project, the largest of its kind in North America, coincides with World Wetlands Day Feb. 2.

Common carp, native to Asia and parts of Europe, are large bottom-dwelling fish. They disrupt wetlands by regularly rooting up vegetation and stirring up silt and sediment, which stops sunlight from reaching other aquatic life.

Research over the past four years has shown vegetation will recover if carp are prevented from entering the marsh during the late spring and summer, They do not overwinter in the marsh because it is too shallow. They were first introduced in Manitoba in the late 1800s as a new food source and spread throughout the Red and Assiniboine rivers, and lakes Winnipeg and Manitoba.

The province's contribution is $500,000. Ducks Unlimited Canada and its partners, including Wildlife Habitat Canada, are contributing $3 million from for a total project contribution of $3.5 million. Ducks Unlimited is supervising the project.

The Manitoba Métis Federation and the Manitoba Habitat Heritage Corporation also plan to have fishers catch the carp as they congregate by the fish screens. Their goal is to expand the market for carp roe.

The average price per kilogram of common carp roe was $2.06 in 2011.