Baltimore checkerspots at Pleasant Valley Conservancy

The Southern Wisconsin Butterfly Association has had its June fieldtrip at PVC for the past seven years. One of the attractions has been the chance to see the Baltimore checkerspot, a small colorful butterfly which is not very common. (In Maryland, where it is the State butterfly, it is considered very rare.)

This year at PVC was no exception, and 23 checkerspots were counted. There were probably a lot more than this count. In fact, they seemed to be all over, even “puddling” in the barn’s dirty gravel apron. (I saw 5 there three days later!)

The whole butterfly trip was great this year, with an exceptional show of butterflies. Checkout the SWBA website for the complete report.

We seem to have the right habitat for checkerspots. Their primary host plant is turtlehead (Chelone glabra), an attractive wetland plant. Our wetland apparently is good habitat for this plant. I should emphasize that we burn the wetland frequently, which may help. In fact, after Fish & Wildlife Service first burned it in 2005 we saw over 100 turtlehead plants in flower!

Another interesting tidbit is that we had turtleheads and checkerspots here even before any restoration work was done. In 1995 we had hired Brian Pruka as an early consultant on our restoration work. He wrote the following analysis of our wetland:

“This Driftless Area wetland is…fed by groundwater from the adjacent bluff. Thus it has fen character to some degree….I tried to locate as many fen-loving species as possible and was delighted to find Turtlehead…which blossoms in late August and early September….Equally exciting was when I sighted a Baltimore Checkerspot butterfly. The Baltimore is one of Wisconsin’s most exotically patterned butterflies….The caterpillar…feeds exclusively on Turtlehead; thus it too is a fen-dependent species.” Wisconsin Wetlands Association Newsletter 1995.

I have compiled a list of over 300 plant species that were present at PVC before any restoration work had begun. The bulk of the species on this list came from Brian Pruka.