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In July 2006, Conservancy staff in Indiana finished the first year of what we plan to be a five-year cycle of what are commonly known as “gentle” releases of Karner blue butterflies into Ivanhoe Dune & Swale Nature Preserve (in Gary, Indiana), the Dupont Natural Area, and Tolleston Ridges Nature Preserve, each hugging the southern rim of Lake Michigan. We also finished the first release of Karner blue butterflies at Howe’s Prairie, part of the eastern portion of Indiana Dunes National Lakeshore.
The national park has been one of our long-standing partners in the effort to reintroduce the Karner blue butterfly into a portion of its former range. Unlike prior years, when we raised the Karner blue butterflies in desk-top incubating units in our office at Calumet College, this year we worked out of the offices of the Indiana Dunes National Lakeshore.
 We are planning on doing these smaller, gentle, releases over time rather than a single large release at once. The idea is to replicate the maximum number of adult butterflies expected during the second flight – about 100 at most of the sites where we are working. Most of our sites will never support a large number of Karner blue butterflies, but a string of small patches of habitat will create a mosaic of sites along the southern rim of Lake Michigan, which we hope to link together to create a “metapopulation” of hundreds to perhaps 1,000 adults.
This year, we placed 355 Karner blue pupae into release nets and virtually all of these emerged as adults at the release sites. The newly released individuals will hopefully overlap with and introduce genetic diversity to any naturally occurring populations at Ivanhoe Dune & Swale, Dupont Natural Area and Tolleston Ridges Nature Preserve. The introduction at Howe’s Prairie was part of the 40-year anniversary of the Indiana Dunes, with a plan to bring this endangered species back to the east unit of the national park.
These reintroductions – and our linkage between these patches – are not possible without (a) the acquisition of appropriate sites for the Karner blue as well as habitat corridors (chiefly along rivers, and railroad and utility rights-of-way) linking those sites (which will permit the population to migrate), and (b) extensive restoration efforts at each site. Returning a site to its original vegetation – including planting over 32,000 lupine plugs (the host plant for the Karner blue butterflies) to date – is both time consuming and absolutely necessary for these tiny blue marvels to take flight and flourish.
The distinctive silvery-gray and blue wings of the Karner Blue once flitted amid wildflowers from New England to Minnesota. Its numbers have plummeted 99 percent in the last 100 years due to habitat destruction. U.S. Fish and Wildlife says the greatest drop — 90 percent — occurred in the last 15 years.
More than six years ago, a wildfire consumed one of its few remaining habitats in Northwest Indiana, Ivanhoe Nature Preserve, which is located close to the heavy industries of Gary. Within a year, this rare butterfly disappeared from the 131-acre preserve. The Conservancy launched an effort to reintroduce this federally-endangered butterfly.
Project manager Paul Labus and his team spent months hand feeding caterpillars leaves of the blue lupine, the Karner Blue’s larval plant food, and planting an abundance of this pea-shaped wildflower.
Building on the success of the reintroduction, the Conservancy is working with federal and state officials to expand its effort to restore Karner blue butterflies to other preserves in northwestern Indiana. | 
