Little sections of the Indiana Dunes provide an oasis in a world that is basically a desert to the Karner blue butterfly.

This beautiful species of butterfly has seen its population nearly disappear over the past century, with a majority of this occurring over the last two decades. As a result, the Karner blue has landed on the federally endangered list.

The Great Lakes states and southern Canada used to have healthy numbers of the butterfly, but now they are primarily seen only in Wisconsin, Michigan and the Indiana Dunes National Lakeshore. The Karner blue is a rather small butterfly with a wingspan of about 1 inch.

The male's top surface is blue with black edges and white margins. The female is similar in color, but with more of a grayish-brown color and orange crescents on its edges.

Two generations of Karner eggs hatch each season. In mid-spring, the initial caterpillars develop from the previous year's eggs. These caterpillars grow into butterflies from their cocoons early in the summer.

The adult butterflies then mate and deposit their eggs on the wild lupine, a small, blue flowering plant. These eggs hatch and the caterpillars will feed on the plants for a few weeks.

The final generation will turn into butterflies later in the summer. They will only take flight two times during the summer.

The butterfly's ability to procreate is mainly dependent on the lupine plant, which grows in dry soils in open and shaded clearings. The oak savanna areas of the Dunes are ideal for the plant.

Years of wildfire suppression, along with human development, have nearly eliminated the environment for the lupine growth, which has isolated populations of the butterfly by making them susceptible to environmental changes. Without fires, the open savannas are overrun with grasses and other plants that squeeze out the lupine.

Indiana Dunes officials have administered multiple prescribed burns over the years in the savanna areas in an effort to clear trees and brush. The hope is that those will create a better habitat for the lupine plant and Karner blue butterfly.