M-10 - Silver-Calvin Creeks

Site Description

The Silver-Calvin Creeks site is located on the eastern coast of Manitowoc County a few miles south of the City of Manitowoc. This site combines four smaller wetland sites identified in the Coastal Wetlands of Manitowoc County report (Water Resources Management Graduate Students, 1998) and is under a mixture of public and private ownerships. Both Silver and Calvin creeks have down cut through bluffs of clayey reddish till to form "coastal canyon" wetlands as the drainage network developed after the retreat from the former Lake Nipissing lake level.

At this site the canyons and stream corridors feature a mixture of wetland types including white cedar dominated bluff face seeps, hardwood swamps, emergent marshes, and shrub swamps. The wetlands have all suffered various degrees of disturbance. Upland forest with dominants that include both conifers and hardwoods cover the balance of the corridor.

Both Calvin and Silver creeks are moderate-gradient streams with gravel and rubble bottoms. Fish including smelt and suckers spawn here in the spring. The stream corridors are narrow and bordered by areas developed for residential or agricultural uses. The site does provide a diversity of habitats for native plants and animals, but many of these habitats are small. Even small patches of remnant forest can be quite significant as stopovers for migratory birds.

Additional Comments

Although small, this relatively undeveloped site is significant in this heavily developed stretch of Lake Michigan shoreline. However, conservation limitations include small size, isolation, past disturbances, and the impacts of surrounding land use.