The oak savanna and sand prairie ecosystems that support the Karner blue butterfly are almost as rare as the butterfly itself. Small patches of this habitat exist in the far southern portions of Lake Huron (around the Pinery-Kettle Point area).

 

The Karner blue requires wild lupine, which is the only plant the Karner blue caterpillar is known to feed on, and therefore is critical to the butterfly’s survival. Other plants are also important to the adult butterfly, such as butterfly weed, horsemint, orange hawkweed, ox-eye-daisy and hairy puccoon.

 

The male appearance is a light blue with sivery, indigo coloured wings. The female is greyish-brown, especially on the outer portions of its wings, to blue on the topside.