Riveredge Nature Center is working with the Milwaukee Public Museum to maintain a population of the state endangered swamp metalmark butterfly in it’s sanctuary. With help of volunteers and Riveredge’s Habitat Healers management is being conducted to maintain this butterfly’s habitat.

Background Information

The metalmarks are small butterflies that occur principally in the tropics of the New World.  Many species are very attractive and show gorgeous colors.  In the United States, where only a few species dwell, they are for the most part dull or nondescript butterflies as regards the upper surfaces.  The undersides, however, are much more attractive and often display tiny metallic markings or lines. Adult males have more pointed forewings and reduced forelegs; while females have six well developed legs.

Swamp metalmark. Photo taken by Sue Borkin.

Swamp metalmark. Photo taken by Sue Borkin.

In the eastern half of the country there are three native metalmarks but only the swamp metalmark (Calephelis mutica) occurs in Wisconsin.

The swamp metalmark is a rusty orange-brown which is cobwebbed with darker markings. Two parallel rows of metallic lead-colored dots follow its upper wing margins from which it gets its name. The undersides are remarkably bright and uniform shade of golden orange, heavily speckled with tiny, variously shaped black markings. This tiny dime-sized butterfly has a wing span that is less than one inch.

Range

In Wisconsin the adults possibly occur in swampy locations throughout the southern part of the state where the food plant grows, but may be very easily overlooked because of their later flight period, small size, and strict choice of habitat.  As of November 2009 there are only two confirmed populations including one reintroduction at Riveredge Nature Center in Ozaukee County and one in the Northern Kettle Moraine State Forest in Fond du Lac County.

This species is reported as rare to endangered throughout its range, which includes Michigan, Ohio, Indiana, Kentucky (one record), Illinois, Arkansas and Missouri.

Habitat Management

The Habitat Management Plan presented below  reaches beyond the goal of maintaining the high-quality condition of the sanctuary, to outline a strategy that specifically addresses conserving and enhancing breeding habitat for the state-endangered swamp metalmark on the property.  Program activities with volunteers and visitors are already restricted in metalmark habitats in order to protect the sensitive fen wetlands from degradation caused by trampling, but much more can be done.

SMM Mgt Plan 2012